International Nuclear Information System (INIS)
Basdevant, J.L.; Dalibart, J.
1997-01-01
This pedagogical book gives an initiation to the principles and practice of quantum mechanics. A large part is devoted to experimental facts and to their analysis: concrete facts, phenomena and applications related to fundamental physics, elementary particles, astrophysics, high-technology, semi-conductors, micro-electronics and lasers. The book is divided in 22 chapters dealing with: quantum phenomena, wave function and Schroedinger equation, physical units and measurements, energy quantification of some simple systems, Hilbert space, Dirac formalism and quantum mechanics postulates, two-state systems and ammonia Maser principle, bands theory and crystals conductibility, commutation of observables, Stern and Gerlach experiment, approximation methods, kinetic momentum in quantum mechanics, first description of atoms, 1/2 spin formalism and magnetic resonance, Lagrangian, Hamiltonian and Lorentz force in quantum mechanics, addition of kinetic momenta and fine and hyper-fine structure of atomic lines, identical particle systems and Pauli principle, qualitative physics and scale of size of some microscopic and macroscopic phenomena, systems evolution, collisions and cross sections, invariance and conservation laws, quantum mechanics and astrophysics, and historical aspects of quantum mechanics. (J.S.)
Le Bellac, Michel
2006-03-01
Quantum physics allows us to understand the nature of the physical phenomena which govern the behavior of solids, semi-conductors, lasers, atoms, nuclei, subnuclear particles and light. In Quantum Physics, Le Bellac provides a thoroughly modern approach to this fundamental theory. Throughout the book, Le Bellac teaches the fundamentals of quantum physics using an original approach which relies primarily on an algebraic treatment and on the systematic use of symmetry principles. In addition to the standard topics such as one-dimensional potentials, angular momentum and scattering theory, the reader is introduced to more recent developments at an early stage. These include a detailed account of entangled states and their applications, the optical Bloch equations, the theory of laser cooling and of magneto-optical traps, vacuum Rabi oscillations, and an introduction to open quantum systems. This is a textbook for a modern course on quantum physics, written for advanced undergraduate and graduate students. Completely original and contemporary approach, using algebra and symmetry principles Introduces recent developments at an early stage, including many topics that cannot be found in standard textbooks. Contains 130 physically relevant exercises
Quantum Physics for Beginners.
Strand, J.
1981-01-01
Suggests a new approach for teaching secondary school quantum physics. Reviews traditional approaches and presents some characteristics of the three-part "Quantum Physics for Beginners" project, including: quantum physics, quantum mechanics, and a short historical survey. (SK)
Ficek, Zbigniew
2016-01-01
The textbook introduces students to the main ideas of quantum physics and the basic mathematical methods and techniques used in the fields of advanced quantum physics, atomic physics, laser physics, nanotechnology, quantum chemistry, and theoretical mathematics. The textbook explains how microscopic objects (particles) behave in unusual ways, giving rise to what's called quantum effects. It contains a wide range of tutorial problems from simple confidence-builders to fairly challenging exercises that provide adequate understanding of the basic concepts of quantum physics.
Haroche, Serge
2013-01-01
From the infinitely small to the infinitely big, covering over 60 spatial orders of magnitude, quantum theory is used as much to describe the still largely mysterious vibrations of the microscopic strings that could be the basic constituents of the Universe, as to explain the fluctuations of the microwave radiation reaching us from the depths of outer space. Serge Haroche tells us about the scientific theory that revolutionised our understanding of nature and made an extraordinary contributio...
Nonlinear Dynamics In Quantum Physics -- Quantum Chaos and Quantum Instantons
Kröger, H.
2003-01-01
We discuss the recently proposed quantum action - its interpretation, its motivation, its mathematical properties and its use in physics: quantum mechanical tunneling, quantum instantons and quantum chaos.
Quantum Physics Without Quantum Philosophy
Dürr, Detlef; Zanghì, Nino
2013-01-01
It has often been claimed that without drastic conceptual innovations a genuine explanation of quantum interference effects and quantum randomness is impossible. This book concerns Bohmian mechanics, a simple particle theory that is a counterexample to such claims. The gentle introduction and other contributions collected here show how the phenomena of non-relativistic quantum mechanics, from Heisenberg's uncertainty principle to non-commuting observables, emerge from the Bohmian motion of particles, the natural particle motion associated with Schrödinger's equation. This book will be of value to all students and researchers in physics with an interest in the meaning of quantum theory as well as to philosophers of science.
Holzner, Steve
2013-01-01
Quantum Physics For Dummies, Revised Edition helps make quantum physics understandable and accessible. From what quantum physics can do for the world to understanding hydrogen atoms, readers will get complete coverage of the subject, along with numerous examples to help them tackle the tough equations. Compatible with classroom text books and courses, Quantum Physics For Dummies, Revised Edition lets students study at their own paces and helps them prepare for graduate or professional exams. Coverage includes: The Schrodinger Equation and its Applications The Foundations of Quantum Physics Vector Notation Spin Scattering Theory, Angular Momentum, and more From the Back Cover Your plain-English guide to understanding and working with the micro world Quantum physics -- also called quantum mechanics or quantum field theory -- can be daunting for even the most dedicated student or enthusiast of science, math, or physics. This friendly, concise guide makes this challenging subject understandable and accessible, fr...
Measurement in quantum physics
International Nuclear Information System (INIS)
Danos, M.; Kieu, T.D.; Columbia Univ., New York, NY
1997-01-01
The conceptual problems in quantum mechanics - including the collapse of the wave functions, the particle-wave duality, the meaning of measurement-arise from the need to ascribe particle character to the wave function, which describes only the wave aspects. It is demonstrated that all these problems can be resolved when working instead with quantum fields, which have both wave and particle character. The predictions of quantum physics, including Bell's inequalities, remain unchanged from the standard treatments of quantum mechanics. 16 refs
International Nuclear Information System (INIS)
Basdevant, J.L.
1983-01-01
This book is the second part of the physic lectures on quantum mechanics from Ecole Polytechnique. It contains some physic complements a little more thoroughly studied, mathematical complements to which refer, and an exercise and problem collection [fr
Quantum physics meets biology.
Arndt, Markus; Juffmann, Thomas; Vedral, Vlatko
2009-12-01
Quantum physics and biology have long been regarded as unrelated disciplines, describing nature at the inanimate microlevel on the one hand and living species on the other hand. Over the past decades the life sciences have succeeded in providing ever more and refined explanations of macroscopic phenomena that were based on an improved understanding of molecular structures and mechanisms. Simultaneously, quantum physics, originally rooted in a world-view of quantum coherences, entanglement, and other nonclassical effects, has been heading toward systems of increasing complexity. The present perspective article shall serve as a "pedestrian guide" to the growing interconnections between the two fields. We recapitulate the generic and sometimes unintuitive characteristics of quantum physics and point to a number of applications in the life sciences. We discuss our criteria for a future "quantum biology," its current status, recent experimental progress, and also the restrictions that nature imposes on bold extrapolations of quantum theory to macroscopic phenomena.
International Nuclear Information System (INIS)
Fomin, Vladimir M.
2014-01-01
Presents the new class of materials of quantum rings. Provides an elemental basis for low-cost high-performance devices promising for electronics, optoelectronics, spintronics and quantum information processing. Explains the physical properties of quantum rings to cover a gap in scientific literature. Presents the application of most advanced nanoengineering and nanocharacterization techniques. This book deals with a new class of materials, quantum rings. Innovative recent advances in experimental and theoretical physics of quantum rings are based on the most advanced state-of-the-art fabrication and characterization techniques as well as theoretical methods. The experimental efforts allow to obtain a new class of semiconductor quantum rings formed by capping self-organized quantum dots grown by molecular beam epitaxy. Novel optical and magnetic properties of quantum rings are associated with non-trivial topologies at the nanoscale. An adequate characterization of quantum rings is possible on the basis of modern characterization methods of nanostructures, such as Scanning Tunneling Microscopy. A high level of complexity is demonstrated to be needed for a dedicated theoretical model to adequately represent the specific features of quantum rings. The findings presented in this book contribute to develop low-cost high-performance electronic, spintronic, optoelectronic and information processing devices based on quantum rings.
International Nuclear Information System (INIS)
Basdevant, J.L.
1983-01-01
From important experiment descriptions (sometimes, intentionally simplified), the essential concepts in Quantum Mechanics are first introduced. Wave function notion is described, Schroedinger equation is established, and, after applications rich in physical signification, quantum state and Hilbert space formalism are introduced, which will help to understand many essential phenomena. Then the quantum mechanic general formulation is written and some important consequences are deduced. This formalism is applied to a simple physical problem series (angular momentum, hydrogen atom, etc.) aiming at assimilating the theory operation and its application [fr
Quantum physics; Physique quantique
Energy Technology Data Exchange (ETDEWEB)
Basdevant, J.L.; Dalibart, J. [Ecole Polytechnique, 75 - Paris (France)
1997-12-31
This pedagogical book gives an initiation to the principles and practice of quantum mechanics. A large part is devoted to experimental facts and to their analysis: concrete facts, phenomena and applications related to fundamental physics, elementary particles, astrophysics, high-technology, semi-conductors, micro-electronics and lasers. The book is divided in 22 chapters dealing with: quantum phenomena, wave function and Schroedinger equation, physical units and measurements, energy quantification of some simple systems, Hilbert space, Dirac formalism and quantum mechanics postulates, two-state systems and ammonia Maser principle, bands theory and crystals conductibility, commutation of observables, Stern and Gerlach experiment, approximation methods, kinetic momentum in quantum mechanics, first description of atoms, 1/2 spin formalism and magnetic resonance, Lagrangian, Hamiltonian and Lorentz force in quantum mechanics, addition of kinetic momenta and fine and hyper-fine structure of atomic lines, identical particle systems and Pauli principle, qualitative physics and scale of size of some microscopic and macroscopic phenomena, systems evolution, collisions and cross sections, invariance and conservation laws, quantum mechanics and astrophysics, and historical aspects of quantum mechanics. (J.S.) refs.
International Nuclear Information System (INIS)
Durstberger, K.; Hasegawa, Y.; Klepp, J.; Sulyok, G.; Rauch, H.
2008-01-01
Full text: Fundamental quantum properties like quantum coherence and entanglement are among the most interesting features of quantum mechanics. The physical system of interest is the (massive) neutron subjected to interferometric and polarimetric measurements. Neutrons are proper objects for a study of quantum mechanical behavior: they allow for rather easy experimental control and the neutron spin is the simplest two-level system with easy manipulation by magnetic fields. In combination with interferometric measurements the system has enough intrinsic richness to show interesting quantum features such as entanglement. The coupling of the neutron to an external magnetic field allows for selective manipulations of the spinor quantum states. This can be used, on the one hand, to create entangled states where the entanglement occurs between different degrees of freedom (e.g. spin and path) and, on the other hand, one can introduce dephasing and decoherence by varying magnetic fields. We investigate different kinds of entanglement for the neutron system and mechanisms for decoherence and dephasing. We discuss weak measurements and their realization for neutrons where information about the system can be revealed without disturbing the system too much. Beyond the theoretical work we develop experimental strategies to check the results directly in suitably designed experiments. The experimental work is done at the Institute Laue-Langvine (ILL) in Grenoble, France. (author)
International Nuclear Information System (INIS)
Levy-Leblond, J.M.
1988-01-01
A novel theory, when it appears, cannot but use old words to label new concepts. In some cases, the extension in meaning thus conferred to standard terminology is natural enough so that the transfer may not lead to too many misunderstandings. Most often, however, and especially when the conceptual gap between the old and the new theory is a wide one, a casual transfer of terminology may lead to epistemological and pedagogical difficulties. This situation has been and still is particularly serious in quantum theory. Here, the careless use of words taken from classical physics - such as quantum 'mechanics', 'uncertainty', etc. -, is compounded by the uncritical use of interpretative terms linked to a definite, if implicit, philosophical point of view - such as ''complementarity'', ''wave-particle duality'', ''observables'', etc. While these words and the ideas they represent have played a major role in the birth of quantum physics more than half a century ago, they are not longer necessarily the best ones to be used today. It is not argued here that we should start afresh and create from scratch a supposedly adequate vocabulary for quantum physics. Abuse of language certainly is unavoidable in science as it is in any human communication; without it, language would not live and evolve. But, at the very least, let us recognize it for what it is, so that it does not add its troubles to already complicated issues. And in some definite instances, still, a willing effort to replace specially ambiguous words might be worthwhile. (orig.)
Theoretical physics. Quantum mechanics
International Nuclear Information System (INIS)
Rebhan, Eckhard
2008-01-01
From the first in two comprehensive volumes appeared Theoretical Physics of the author by this after Mechanics and Electrodynamics also Quantum mechanics appears as thinner single volume. First the illustrative approach via wave mechanics is reproduced. The more abstract Hilbert-space formulation introduces the author later by postulates, which are because of the preceding wave mechanics sufficiently plausible. All concepts of quantum mechanics, which contradict often to the intuitive understanding formed by macroscopic experiences, are extensively discussed and made by means of many examples as well as problems - in the largest part provided with solutions - understandable. To the interpretation of quantum mechanics an extensive special chapter is dedicated. this book arose from courses on theoretical physics, which the author has held at the Heinrich-Heine University in Duesseldorf, and was in numerous repetitions fitted to the requirement of the studyings. it is so designed that it is also after the study suited as reference book or for the renewing. All problems are very thoroughly and such extensively studied that each step is separately reproducible. About motivation and good understandability is cared much
Increasing complexity with quantum physics.
Anders, Janet; Wiesner, Karoline
2011-09-01
We argue that complex systems science and the rules of quantum physics are intricately related. We discuss a range of quantum phenomena, such as cryptography, computation and quantum phases, and the rules responsible for their complexity. We identify correlations as a central concept connecting quantum information and complex systems science. We present two examples for the power of correlations: using quantum resources to simulate the correlations of a stochastic process and to implement a classically impossible computational task.
Physics of quantum computation
International Nuclear Information System (INIS)
Belokurov, V.V.; Khrustalev, O.A.; Sadovnichij, V.A.; Timofeevskaya, O.D.
2003-01-01
In the paper, the modern status of the theory of quantum computation is considered. The fundamental principles of quantum computers and their basic notions such as quantum processors and computational basis states of the quantum Turing machine as well as the quantum Fourier transform are discussed. Some possible experimental realizations on the basis of NMR methods are given
Hidden worlds in quantum physics
Gouesbet, Gérard
2014-01-01
The past decade has witnessed a resurgence in research and interest in the areas of quantum computation and entanglement. This new book addresses the hidden worlds or variables of quantum physics. Author Gérard Gouesbet studied and worked with a former student of Louis de Broglie, a pioneer of quantum physics. His presentation emphasizes the history and philosophical foundations of physics, areas that will interest lay readers as well as professionals and advanced undergraduate and graduate students of quantum physics. The introduction is succeeded by chapters offering background on relevant concepts in classical and quantum mechanics, a brief history of causal theories, and examinations of the double solution, pilot wave, and other hidden-variables theories. Additional topics include proofs of possibility and impossibility, contextuality, non-locality, classification of hidden-variables theories, and stochastic quantum mechanics. The final section discusses how to gain a genuine understanding of quantum mec...
Philosophy of physics quantum theory
Maudlin, Tim
2019-01-01
In this book, Tim Maudlin, one of the worlds leading philosophers of physics, offers a sophisticated, original introduction to the philosophy of quantum mechanics. The briefest, clearest, and most refined account of his influential approach to the subject, the book will be invaluable to all students of philosophy and physics. Quantum mechanics holds a unique place in the history of physics. It has produced the most accurate predictions of any scientific theory, but, more astonishing, there has never been any agreement about what the theory implies about physical reality. Maudlin argues that the very term quantum theory is a misnomer. A proper physical theory should clearly describe what is there and what it doesyet standard textbooks present quantum mechanics as a predictive recipe in search of a physical theory. In contrast, Maudlin explores three proper theories that recover the quantum predictions: the indeterministic wavefunction collapse theory of Ghirardi, Rimini, and Weber; the deterministic ...
Relationism of quantum physics
International Nuclear Information System (INIS)
Chylinski, Z.
1995-01-01
This paper develops the hypothesis of quantum relationism. Quantum relationism is compared and contrasted with the Cartesian eventism, which is the ontology behind the conventional local quantum field theory. In more technical terms the paper deals with a relativistic description of bound quantal systems which, in Author's opinion, provide an ideal testing ground for his hypothesis. (author)
Quantum physics and relational ontology
Energy Technology Data Exchange (ETDEWEB)
Cordovil, Joao [Center of Philosophy of Sciences of University of Lisbon (Portugal)
2013-07-01
The discovery of the quantum domain of reality put a serious ontological challenge, a challenge that is still well present in the recent developments of Quantum Physics. Physics was conceived from an atomistic conception of the world, reducing it, in all its diversity, to two types of entities: simple, individual and immutable entities (atoms, in metaphysical sense) and composite entities, resulting solely from combinations. Linear combinations, additive, indifferent to the structure or to the context. However, the discovery of wave-particle dualism and the developments in Quantum Field Theories and in Quantum Nonlinear Physical, showed that quantum entities are not, in metaphysical sense, neither simple, nor merely the result of linear (or additive) combinations. In other words, the ontological foundations of Physics revealed as inadequate to account for the nature of quantum entities. Then a fundamental challenge arises: How to think the ontic nature of these entities? In my view, this challenge appeals to a relational and dynamist ontology of physical entities. This is the central hypothesis of this communication. In this sense, this communication has two main intentions: 1) positively characterize this relational and dynamist ontology; 2) show some elements of its metaphysical suitability to contemporary Quantum Physics.
Quantum computing for physics research
International Nuclear Information System (INIS)
Georgeot, B.
2006-01-01
Quantum computers hold great promises for the future of computation. In this paper, this new kind of computing device is presented, together with a short survey of the status of research in this field. The principal algorithms are introduced, with an emphasis on the applications of quantum computing to physics. Experimental implementations are also briefly discussed
Physical foundations of quantum electronics
Klyshko, David; Kulik, Sergey
2011-01-01
This concise textbook introduces a graduate student to the various fields of physics related to the interaction between radiation and matter. The scope of the book is very broad, ranging from nonlinear to quantum optics and from quantum transitions in atoms to the dispersion of polaritons in continuous media. The author, Professor David Klyshko (1929-2000), is one of the founders of modern quantum optics, renowned for his theory of Spontaneous Parametric Down-Conversion (SPDC) and its applications in quantum metrology and the optics of nonclassical light. Most parts of the book contain the lec
Physical implementation of quantum walks
Manouchehri, Kia
2013-01-01
Given the extensive application of random walks in virtually every science related discipline, we may be at the threshold of yet another problem solving paradigm with the advent of quantum walks. Over the past decade, quantum walks have been explored for their non-intuitive dynamics, which may hold the key to radically new quantum algorithms. This growing interest has been paralleled by a flurry of research into how one can implement quantum walks in laboratories. This book presents numerous proposals as well as actual experiments for such a physical realization, underpinned by a wide range of
Quantum physics a beginner's guide
Rae, Alastair I M
2005-01-01
As Alastair Rae points out in his introduction, ""quantum physics is not rocket science"". It may have gained a reputation as the theory that no one really understands, but its practical applications are all around us in everyday life. If it were not for quantum physics, computers would not function, metals would not conduct electricity, and the power stations that heat our homes would not produce energy. Assuming no prior scientific or mathematical knowledge, this clear and concise introduction provides a step-by-step guide to quantum theory, right from the very basic principles to the most c
Quantum Electronics for Atomic Physics
Nagourney, Warren
2010-01-01
Quantum Electronics for Atomic Physics provides a course in quantum electronics for researchers in atomic physics. The book covers the usual topics, such as Gaussian beams, cavities, lasers, nonlinear optics and modulation techniques, but also includes a number of areas not usually found in a textbook on quantum electronics. It includes such practical matters as the enhancement of nonlinear processes in a build-up cavity, impedance matching into a cavity, laser frequencystabilization (including servomechanism theory), astigmatism in ring cavities, and atomic/molecular spectroscopic techniques
Quantum physics and statistical physics. 5. ed.
International Nuclear Information System (INIS)
Alonso, Marcelo; Finn, Edward J.
2012-01-01
By logical and uniform presentation this recognized introduction in modern physics treats both the experimental and theoretical aspects. The first part of the book deals with quantum mechanics and their application to atoms, molecules, nuclei, solids, and elementary particles. The statistical physics with classical statistics, thermodynamics, and quantum statistics is theme of the second part. Alsonso and Finn avoid complicated mathematical developments; by numerous sketches and diagrams as well as many problems and examples they make the reader early and above all easily understandably familiar with the formations of concepts of modern physics.
On nonlocality in quantum physics
International Nuclear Information System (INIS)
Spasskij, B.I.; Moskovskij, A.V.
1984-01-01
The properties of nonlocality of quantum objects are considered on the example of the Aharonov-Bohm, effect Brown-Twiss effect, Einstein-Podolsky-Rosen paradox. These effects demonstrate inherent features of specific integrity in quantum objects. The term ''nonlocality'' is considered as a ''quantum analog'' of the notion of long range. Experiments on checking the Bell inequalities for fulfilment are described. The inequalities permit to solve which of the quantum mechanics interpretations is correct either the Einstein interpretation according to which the quantum system properties exist as elements of physical reality irrespective of their observation, or the Copenhagen one, according to which the microsystem properties described by noncommuting operators do not exist irrespective of measurement means
Quantum Physics Illusion or Reality?
Rae, Alastair I M
2004-01-01
Quantum physics is believed to be the fundamental theory underlying our understanding of the physical universe. However, it is based on concepts and principles that have always been difficult to understand and controversial in their interpretation. This book aims to explain these issues using a minimum of technical language and mathematics. After a brief introduction to the ideas of quantum physics, the problems of interpretation are identified and explained. The rest of the book surveys, describes and criticises a range of suggestions that have been made with the aim of resolving these proble
International Nuclear Information System (INIS)
Gasiorowicz, S.
2002-01-01
The following topics are dealt with: wave packets and uncertainty relation, Schroedinger equation, eigenfunctions and eigenvalues, one-dimensional potentials, wave mechanics, quantum operators, angular momentum, hydrogen atom, interaction of electrons with electromagnetic fields, operators, matrices and spin, perturbation theory, helium atom, molecules, atomic radiation, radiation theory, collision processes
Topology change and quantum physics
International Nuclear Information System (INIS)
Balachandran, A.P.; Marmo, G.; Simoni, A.
1995-01-01
The role of topology in elementary quantum physics is discussed in detail. It is argued that attributes of classical spatial topology emerge from properties of state vectors with suitably smooth time evolution. Equivalently, they emerge from considerations on the domain of the quantum Hamiltonian, this domain being often specified by boundary conditions in elementary quantum physics. Examples are presented where classical topology is changed by smoothly altering the boundary conditions. When the parameters labelling the latter are treated as quantum variables, quantum states need not give a well-defined classical topology, instead they can give a quantum superposition of such topologies. An existing argument of Sorkin based on the spin-statistics connection and indicating the necessity of topology change in quantum gravity is recalled. It is suggested therefrom and our results here that Einstein gravity and its minor variants are effective theories of a deeper description with additional novel degrees of freedom. Other reasons for suspecting such a microstructure are also summarized. (orig.)
Topology change and quantum physics
International Nuclear Information System (INIS)
Balachandran, A.P.; Marmo, G.; Simoni, A.
1995-03-01
The role of topology in elementary quantum physics is discussed in detail. It is argued that attributes of classical spatial topology emerge from properties of state vectors with suitably smooth time evolution. Equivalently, they emerge from considerations on the domain of the quantum Hamiltonian, this domain being often specified by boundary conditions in elementary quantum physics. Several examples are presented where classical topology is changed by smoothly altering the boundary conditions. When the parameters labelling the latter are treated as quantum variables, quantum states need not give a well-defined classical topology, instead they can give a quantum superposition of such topologies. An existing argument of Sorkin based on the spin-statistics connection and indicating the necessity of topology change in quantum gravity is recalled. It is suggested therefrom and our results here that Einstein gravity and its minor variants are effective theories of a deeper description with additional novel degrees of freedom. Other reasons for suspecting such a microstructure are also summarized. (author). 22 refs, 3 figs
Physical Realizations of Quantum Computing
Kanemitsu, Shigeru; Salomaa, Martti; Takagi, Shin; Are the DiVincenzo Criteria Fulfilled in 2004 ?
2006-01-01
The contributors of this volume are working at the forefront of various realizations of quantum computers. They survey the recent developments in each realization, in the context of the DiVincenzo criteria, including nuclear magnetic resonance, Josephson junctions, quantum dots, and trapped ions. There are also some theoretical contributions which have relevance in the physical realizations of a quantum computer. This book fills the gap between elementary introductions to the subject and highly specialized research papers to allow beginning graduate students to understand the cutting-edge of r
The physics of quantum mechanics
Binney, James
2014-01-01
The Physics of Quantum Mechanics aims to give students a good understanding of how quantum mechanics describes the material world. It shows that the theory follows naturally from the use of probability amplitudes to derive probabilities. It stresses that stationary states are unphysical mathematical abstractions that enable us to solve the theory's governing equation, the time-dependent Schroedinger equation. Every opportunity is taken to illustrate the emergence of the familiarclassical, dynamical world through the quantum interference of stationary states. The text stresses the continuity be
Finite groups and quantum physics
International Nuclear Information System (INIS)
Kornyak, V. V.
2013-01-01
Concepts of quantum theory are considered from the constructive “finite” point of view. The introduction of a continuum or other actual infinities in physics destroys constructiveness without any need for them in describing empirical observations. It is shown that quantum behavior is a natural consequence of symmetries of dynamical systems. The underlying reason is that it is impossible in principle to trace the identity of indistinguishable objects in their evolution—only information about invariant statements and values concerning such objects is available. General mathematical arguments indicate that any quantum dynamics is reducible to a sequence of permutations. Quantum phenomena, such as interference, arise in invariant subspaces of permutation representations of the symmetry group of a dynamical system. Observable quantities can be expressed in terms of permutation invariants. It is shown that nonconstructive number systems, such as complex numbers, are not needed for describing quantum phenomena. It is sufficient to employ cyclotomic numbers—a minimal extension of natural numbers that is appropriate for quantum mechanics. The use of finite groups in physics, which underlies the present approach, has an additional motivation. Numerous experiments and observations in the particle physics suggest the importance of finite groups of relatively small orders in some fundamental processes. The origin of these groups is unclear within the currently accepted theories—in particular, within the Standard Model.
International Nuclear Information System (INIS)
Spillner, Vera
2011-01-01
This thesis presents a bundle definition for 'scientific understanding' through which the empirically equivalent interpretations of quantum mechanics can be evaluated with respect to the understanding they generate. The definition of understanding is based on a sufficient and necessary criterion, as well as a bundle of conditions - where a theory can be called most understandable whenever it fulfills the highest number of bundle criteria. Thereby the definition of understanding is based on the one hand on the objective number of criteria a theory fulfills, as well as, on the other hand, on the individual's preference of bundle criteria. Applying the definition onto three interpretations of quantum mechanics, the interpretation of David Bohm appears as most understandable, followed by the interpretation of Tim Maudlin and the Kopenhagen interpretation. These three interpretations are discussed in length in my thesis. (orig.)
Uncommon paths in quantum physics
Kazakov, Konstantin V
2014-01-01
Quantum mechanics is one of the most fascinating, and at the same time most controversial, branches of contemporary science. Disputes have accompanied this science since its birth and have not ceased to this day. Uncommon Paths in Quantum Physics allows the reader to contemplate deeply some ideas and methods that are seldom met in the contemporary literature. Instead of widespread recipes of mathematical physics, based on the solutions of integro-differential equations, the book follows logical and partly intuitional derivations of non-commutative algebra. Readers can directly penetrate the
How quantum physics came to Cambridge
International Nuclear Information System (INIS)
McCrea, William
1985-01-01
The paper traces the early stages of quantum physics, in Cambridge, in the 1920's. The mathematicians who inspired a generation of quantum physicists are briefly described, as well as the work of Dirac on quantum mechanics. The author's own contribution to quantum mechanics is outlined, along with other work in physics carried out at that time in Cambridge. (U.K.)
Geometrization of quantum physics
International Nuclear Information System (INIS)
Ol'khov, O.A.
2009-01-01
It is shown that the Dirac equation for a free particle can be considered as a description of specific distortion of the space Euclidean geometry (space topological defect). This approach is based on the possibility of interpretation of the wave function as vector realizing representation of the fundamental group of the closed topological space-time 4-manifold. Mass and spin appear to be topological invariants. Such a concept explains all so-called 'strange' properties of quantum formalism: probabilities, wave-particle duality, nonlocal instantaneous correlation between noninteracting particles (EPR-paradox) and so on. Acceptance of the suggested geometrical concept means rejection of atomistic concept where all matter is considered as consisting of more and more small elementary particles. There are no any particles a priory, before measurement: the notions of particles appear as a result of classical interpretation of the contact of the region of the curved space with a device
Geometrization of quantum physics
Ol'Khov, O. A.
2009-12-01
It is shown that the Dirac equation for free particle can be considered as a description of specific distortion of the space euclidean geometry (space topological defect). This approach is based on possibility of interpretation of the wave function as vector realizing representation of the fundamental group of the closed topological space-time 4-manifold. Mass and spin appear to be topological invariants. Such concept explains all so called “strange” properties of quantum formalism: probabilities, wave-particle duality, nonlocal instantaneous correlation between noninteracting particles (EPR-paradox) and so on. Acceptance of suggested geometrical concept means rejection of atomistic concept where all matter is considered as consisting of more and more small elementary particles. There is no any particles a priori, before measurement: the notions of particles appear as a result of classical interpretation of the contact of the region of the curved space with a device.
Classical and Quantum Thermal Physics
Prasad, R.
2016-11-01
List of figures; List of tables; Preface; Acknowledgement; Dedication; 1. The kinetic theory of gases; 2. Ideal to real gas, viscosity, conductivity and diffusion; 3. Thermodynamics: definitions and Zeroth law; 4. First Law of Thermodynamics and some of its applications; 5. Second Law of Thermodynamics and some of its applications; 6. TdS equations and their applications; 7. Thermodynamic functions, potentials, Maxwell equations, the Third Law and equilibrium; 8. Some applications of thermodynamics to problems of physics and engineering; 9. Application of thermodynamics to chemical reactions; 10. Quantum thermodynamics; 11. Some applications of quantum thermodynamics; 12. Introduction to the thermodynamics of irreversible processes; Index.
Semiotic aspects of quantum physics
International Nuclear Information System (INIS)
Januschke, Eugen
2010-01-01
By means of semiotics it is studied, how it succeeds in quantum physics to make formulas plausible, the basic physical facts of which are not accessible for a common understanding respectively an understanding in the sense of classical physics. Thereby it deals with a generally acknowledged kind of making understandable of certain physical formulas beyond the individual marking distinctly of abilities of explaining and understanding of social phenomena and historical developments, whereby to these formulas each a certain experiment is put on side. The experiment is thereby such chosen that the physical phenomenon, which is described in the formula, is studied in the experiment, so that the formula then results as evaluation of the experiment.
Quantum resonances in physical tunneling
International Nuclear Information System (INIS)
Nieto, M.M.; Truax, D.R.
1985-01-01
It has recently been emphasized that the probability of quantum tunneling is a critical function of the shape of the potential. Applying this observation to physical systems, we point out that in principal information on potential surfaces can be obtained by studying tunneling rates. This is especially true in cases where only spectral data is known, since many potentials yield the same spectrum. 13 refs., 10 figs., 1 tab
Quantum paradoxes and physical reality
Energy Technology Data Exchange (ETDEWEB)
Van der Merwe, Alwyn (Denver Univ., CO (USA). Dept. of Physics) (ed.); Selleri, Franco (Bologna Univ. (Italy). Ist. di Fisica)
1990-01-01
This book is devoted to the most fundamental themes of quantum physics: acausality, wave-particle duality, Einstein-Podolsky-Rosen (EPR) paradox, and so on. These are matters of growing interest for physicists. Several paradoxes have plagued quantum physics since its beginnings, the easiest of which to solve are the paradoxes of completeness (Schroedinger's cat, Wigner's friend, de Broglie's box, etc.). At a deeper level is the paradox of wave-particle duality whose solution probably requires the Einstein-de Broglie picture of atomic systems. The most difficult of them all is the EPR paradox (incompatibility between local realism and quantum theory). The book shows that experimental research can, in principle, solve paradoxes such as EPR and wave-particle duality but that the experiments performed on Bell-type inequalities have instead left the conceptual situation fundamentally unmodified. For a fair understanding of the Einstein-de Broglie and of the Bohr-Heisenberg ideas, an 'internal' lecture of physics is not enough. Such 'external' elements as individual biographies, history of culture, and philosophical preconceptions prove also to be important. (author). refs.; figs.; tabs.
Quantum paradoxes and physical reality
International Nuclear Information System (INIS)
Van der Merwe, Alwyn; Selleri, Franco
1990-01-01
This book is devoted to the most fundamental themes of quantum physics: acausality, wave-particle duality, Einstein-Podolsky-Rosen (EPR) paradox, and so on. These are matters of growing interest for physicists. Several paradoxes have plagued quantum physics since its beginnings, the easiest of which to solve are the paradoxes of completeness (Schroedinger's cat, Wigner's friend, de Broglie's box, etc.). At a deeper level is the paradox of wave-particle duality whose solution probably requires the Einstein-de Broglie picture of atomic systems. The most difficult of them all is the EPR paradox (incompatibility between local realism and quantum theory). The book shows that experimental research can, in principle, solve paradoxes such as EPR and wave-particle duality but that the experiments performed on Bell-type inequalities have instead left the conceptual situation fundamentally unmodified. For a fair understanding of the Einstein-de Broglie and of the Bohr-Heisenberg ideas, an 'internal' lecture of physics is not enough. Such 'external' elements as individual biographies, history of culture, and philosophical preconceptions prove also to be important. (author). refs.; figs.; tabs
Quantum physics in one dimension
Giamarchi, Thierry
2004-01-01
This book presents in a pedagogical yet complete way correlated systems in one dimension. Recent progress in nanotechnology and material research have made one dimensional systems a crucial part of today's physics. After an introduction to the basic concepts of correlated systems, the book gives a step by step description of the techniques needed to treat one dimension, and discusses the resulting physics. Then specific experimental realizations of one dimensional systems such asspin chains, quantum wires, nanotubes, organic superconductors etc. are examined. Given its progressive and pedagogi
Quantum physics and human language
International Nuclear Information System (INIS)
Hartle, James B
2007-01-01
Human languages employ constructions that tacitly assume specific properties of the limited range of phenomena they evolved to describe. These assumed properties are true features of that limited context, but may not be general or precise properties of all the physical situations allowed by fundamental physics. In brief, human languages contain 'excess baggage' that must be qualified, discarded, or otherwise reformed to give a clear account in the context of fundamental physics of even the everyday phenomena that the languages evolved to describe. The surest route to clarity is to express the constructions of human languages in the language of fundamental physical theory, not the other way around. These ideas are illustrated by an analysis of the verb 'to happen' and the word 'reality' in special relativity and the modern quantum mechanics of closed systems
Quantum physics an introduction based on photons
Lvovsky, A I
2018-01-01
This textbook is intended to accompany a two-semester course on quantum mechanics for physics students. Along with the traditional material covered in such a course (states, operators, Schrödinger equation, hydrogen atom), it offers in-depth discussion of the Hilbert space, the nature of measurement, entanglement, and decoherence – concepts that are crucial for the understanding of quantum physics and its relation to the macroscopic world, but rarely covered in entry-level textbooks. The book uses a mathematically simple physical system – photon polarization – as the visualization tool, permitting the student to see the entangled beauty of the quantum world from the very first pages. The formal concepts of quantum physics are illustrated by examples from the forefront of modern quantum research, such as quantum communication, teleportation and nonlocality. The author adopts a Socratic pedagogy: The student is guided to develop the machinery of quantum physics independently by solving sets of carefully ...
Quantum mechanics for applied physics and engineering
Fromhold, Albert T
2011-01-01
This excellent text, directed to upper-level undergraduates and graduate students in engineering and applied physics, introduces the fundamentals of quantum mechanics, emphasizing those aspects of quantum mechanics and quantum statistics essential to an understanding of solid-state theory. A heavy background in mathematics and physics is not required beyond basic courses in calculus, differential equations, and calculus-based elementary physics.The first three chapters introduce quantum mechanics (using the Schrödinger equations), quantum statistics, and the free-electron theory of metals. Ch
Problems and solutions in quantum physics
Ficek, Zbigniew
2016-01-01
This book contains tutorial problems with solutions for the textbook Quantum Physics for Beginners. The reader studying the abstract field of quantum physics needs to solve plenty of practical, especially quantitative, problems. This book places emphasis on basic problems of quantum physics together with some instructive, simulating, and useful applications. A considerable range of complexity is presented by these problems, and not too many of them can be solved using formulas alone.
Classical and quantum thermal physics
Prasad, R
2016-01-01
Covering essential areas of thermal physics, this book includes kinetic theory, classical thermodynamics, and quantum thermodynamics. The text begins by explaining fundamental concepts of the kinetic theory of gases, viscosity, conductivity, diffusion, and the laws of thermodynamics and their applications. It then goes on to discuss applications of thermodynamics to problems of physics and engineering. These applications are explained with the help of P-V and P-S-H diagrams where necessary and are followed by a large number of solved examples and unsolved exercises. The book includes a dedicated chapter on the applications of thermodynamics to chemical reactions. Each application is explained by taking the example of an appropriate chemical reaction, where all technical terms are explained and complete mathematical derivations are worked out in steps starting from the first principle.
Quantum Physics in One Dimension
International Nuclear Information System (INIS)
Logan, David
2004-01-01
To a casual ostrich the world of quantum physics in one dimension may sound a little one-dimensional, suitable perhaps for those with an unhealthy obsession for the esoteric. Nothing of course could be further from the truth. The field is remarkably rich and broad, and for more than fifty years has thrown up innumerable challenges. Theorists, realising that the role of interactions in 1D is special and that well known paradigms of higher dimensions (Fermi liquid theory for example) no longer apply, took up the challenge of developing new concepts and techniques to understand the undoubted peculiarities of one-dimensional systems. And experimentalists have succeeded in turning pipe dreams into reality, producing an impressive and ever increasing array of experimental realizations of 1D systems, from the molecular to the mesoscopic - spin and ladder compounds, organic superconductors, carbon nanotubes, quantum wires, Josephson junction arrays and so on. Many books on the theory of one-dimensional systems are however written by experts for experts, and tend as such to leave the non-specialist a touch bewildered. This is understandable on both fronts, for the underlying theoretical techniques are unquestionably sophisticated and not usually part of standard courses in many-body theory. A brave author it is then who aims to produce a well rounded, if necessarily partial, overview of quantum physics in one dimension, accessible to a beginner yet taking them to the edge of current research, and providing en route a thorough grounding in the fundamental ideas, basic methods and essential phenomenology of the field. It is of course the brave who succeed in this world, and Thierry Giamarchi does just that with this excellent book, written by an expert for the uninitiated. Aimed in particular at graduate students in theoretical condensed matter physics, and assuming little theoretical background on the part of the reader (well just a little), Giamarchi writes in a
Coherent states in quantum physics
Gazeau, Jean-Pierre
2009-01-01
This self-contained introduction discusses the evolution of the notion of coherent states, from the early works of Schrödinger to the most recent advances, including signal analysis. An integrated and modern approach to the utility of coherent states in many different branches of physics, it strikes a balance between mathematical and physical descriptions.Split into two parts, the first introduces readers to the most familiar coherent states, their origin, their construction, and their application and relevance to various selected domains of physics. Part II, mostly based on recent original results, is devoted to the question of quantization of various sets through coherent states, and shows the link to procedures in signal analysis. Title: Coherent States in Quantum Physics Print ISBN: 9783527407095 Author(s): Gazeau, Jean-Pierre eISBN: 9783527628292 Publisher: Wiley-VCH Dewey: 530.12 Publication Date: 23 Sep, 2009 Pages: 360 Category: Science, Science: Physics LCCN: Language: English Edition: N/A LCSH:
Innovative quantum technologies for microgravity fundamental physics and biological research
Kierk, I. K.
2002-01-01
This paper presents a new technology program, within the fundamental physics, focusing on four quantum technology areas: quantum atomics, quantum optics, space superconductivity and quantum sensor technology, and quantum field based sensor and modeling technology.
Quantum Sensing for High Energy Physics
Energy Technology Data Exchange (ETDEWEB)
Ahmed, Zeeshan; et al.
2018-03-29
Report of the first workshop to identify approaches and techniques in the domain of quantum sensing that can be utilized by future High Energy Physics applications to further the scientific goals of High Energy Physics.
Shrinked systems. Quantum physics on new paths
International Nuclear Information System (INIS)
Audretsch, J.
2005-01-01
This introducing textbook for students of higher semesters of physics, chemistry, and informatics treats a in latest time dynamically expanding field of physics. This book deals among others with the themes quantum information theory, quantum communications, quantum computing, teleportation, hidden parameters, which-way-marking, quantum measuring process, POVM, quantum channels and mediates by this not only a deepened understanding of quantum theory but also basic science, in order to follow the fast development of the field respectively to enter a special field of research. Commented recommendations for further literature as well as exercise problems help the reader to find quickly a founded approach to the theoretical foundations of future key technologies. The book can be made to a base of courses and seminars. Because the required basic knowledge in mathematics and quantum theory is presented in introductory chapters, the book is also suited for the self-study
A quantum physics poetry competition
Susanna Wong
2014-01-01
What do you think happened when six world-renowned poets from six European countries met eight famous CERN scientists to talk about the Universe and the Higgs boson? Six poems about new quantum physics discoveries were born from this exciting collision of literature and science in an intimate and spontaneous setting! Express yourself through poetry: this is the call from POPScience, a European Researchers' Night 2014-15 project supported by CERN. The general public can discover the mysteries of particle physics using a series of texts and thematic videos as well as clips of the meetings of the poets and CERN scientists available on the POPScience website. The Big Bang, an expanding Universe, dark energy, matter, antimatter and supersymmetry: what are they and do they exist? The general public is welcome to give an answer in a poem by signing up to the competition. Poems can be submitted in English, French, Italian, Danish and Spanish; the selected entries will be translated ...
The emerging quantum the physics behind quantum mechanics
Pena, Luis de la; Valdes-Hernandez, Andrea
2014-01-01
This monograph presents the latest findings from a long-term research project intended to identify the physics behind Quantum Mechanics. A fundamental theory for quantum mechanics is constructed from first physical principles, revealing quantization as an emergent phenomenon arising from a deeper stochastic process. As such, it offers the vibrant community working on the foundations of quantum mechanics an alternative contribution open to discussion. The book starts with a critical summary of the main conceptual problems that still beset quantum mechanics. The basic consideration is then introduced that any material system is an open system in permanent contact with the random zero-point radiation field, with which it may reach a state of equilibrium. Working from this basis, a comprehensive and self-consistent theoretical framework is then developed. The pillars of the quantum-mechanical formalism are derived, as well as the radiative corrections of nonrelativistic QED, while revealing the underlying physi...
Lesovik, G B; Lebedev, A V; Sadovskyy, I A; Suslov, M V; Vinokur, V M
2016-09-12
Remarkable progress of quantum information theory (QIT) allowed to formulate mathematical theorems for conditions that data-transmitting or data-processing occurs with a non-negative entropy gain. However, relation of these results formulated in terms of entropy gain in quantum channels to temporal evolution of real physical systems is not thoroughly understood. Here we build on the mathematical formalism provided by QIT to formulate the quantum H-theorem in terms of physical observables. We discuss the manifestation of the second law of thermodynamics in quantum physics and uncover special situations where the second law can be violated. We further demonstrate that the typical evolution of energy-isolated quantum systems occurs with non-diminishing entropy.
Nuclear physics and ideas of quantum chaos
International Nuclear Information System (INIS)
Zelevinsky, V.G.
2002-01-01
The field nowadays called 'many-body quantum chaos' was started in 1939 with the article by I.I. Gurevich studying the regularities of nuclear spectra. The field has been extensively developed recently, both mathematically and in application to mesoscopic systems and quantum fields. We argue that nuclear physics and the theory of quantum chaos are mutually beneficial. Many ideas of quantum chaos grew up from the factual material of nuclear physics; this enrichment still continues to take place. On the other hand, many phenomena in nuclear structure and reactions, as well as the general problem of statistical physics of finite strongly interacting systems, can be understood much deeper with the help of ideas and methods borrowed from the field of quantum chaos. A brief review of the selected topics related to the recent development is presented
Quantum Hamiltonian Physics with Supercomputers
International Nuclear Information System (INIS)
Vary, James P.
2014-01-01
The vision of solving the nuclear many-body problem in a Hamiltonian framework with fundamental interactions tied to QCD via Chiral Perturbation Theory is gaining support. The goals are to preserve the predictive power of the underlying theory, to test fundamental symmetries with the nucleus as laboratory and to develop new understandings of the full range of complex quantum phenomena. Advances in theoretical frameworks (renormalization and many-body methods) as well as in computational resources (new algorithms and leadership-class parallel computers) signal a new generation of theory and simulations that will yield profound insights into the origins of nuclear shell structure, collective phenomena and complex reaction dynamics. Fundamental discovery opportunities also exist in such areas as physics beyond the Standard Model of Elementary Particles, the transition between hadronic and quark–gluon dominated dynamics in nuclei and signals that characterize dark matter. I will review some recent achievements and present ambitious consensus plans along with their challenges for a coming decade of research that will build new links between theory, simulations and experiment. Opportunities for graduate students to embark upon careers in the fast developing field of supercomputer simulations is also discussed
Quantum Hamiltonian Physics with Supercomputers
Energy Technology Data Exchange (ETDEWEB)
Vary, James P.
2014-06-15
The vision of solving the nuclear many-body problem in a Hamiltonian framework with fundamental interactions tied to QCD via Chiral Perturbation Theory is gaining support. The goals are to preserve the predictive power of the underlying theory, to test fundamental symmetries with the nucleus as laboratory and to develop new understandings of the full range of complex quantum phenomena. Advances in theoretical frameworks (renormalization and many-body methods) as well as in computational resources (new algorithms and leadership-class parallel computers) signal a new generation of theory and simulations that will yield profound insights into the origins of nuclear shell structure, collective phenomena and complex reaction dynamics. Fundamental discovery opportunities also exist in such areas as physics beyond the Standard Model of Elementary Particles, the transition between hadronic and quark–gluon dominated dynamics in nuclei and signals that characterize dark matter. I will review some recent achievements and present ambitious consensus plans along with their challenges for a coming decade of research that will build new links between theory, simulations and experiment. Opportunities for graduate students to embark upon careers in the fast developing field of supercomputer simulations is also discussed.
Localization and Entanglement in Relativistic Quantum Physics
Yngvason, Jakob
These notes are a slightly expanded version of a lecture presented in February 2012 at the workshop "The Message of Quantum Science—Attempts Towards a Synthesis" held at the ZIF in Bielefeld. The participants were physicists with a wide range of different expertise and interests. The lecture was intended as a survey of a small selection of the insights into the structure of relativistic quantum physics that have accumulated through the efforts of many people over more than 50 years. (Including, among many others, R. Haag, H. Araki, D. Kastler, H.-J. Borchers, A. Wightman, R. Streater, B. Schroer, H. Reeh, S. Schlieder, S. Doplicher, J. Roberts, R. Jost, K. Hepp, J. Fröhlich, J. Glimm, A. Jaffe, J. Bisognano, E. Wichmann, D. Buchholz, K. Fredenhagen, R. Longo, D. Guido, R. Brunetti, J. Mund, S. Summers, R. Werner, H. Narnhofer, R. Verch, G. Lechner, ….) This contribution discusses some facts about relativistic quantum physics, most of which are quite familiar to practitioners of Algebraic Quantum Field Theory (AQFT) [Also known as Local Quantum Physics (Haag, Local quantum physics. Springer, Berlin, 1992).] but less well known outside this community. No claim of originality is made; the goal of this contribution is merely to present these facts in a simple and concise manner, focusing on the following issues: Explaining how quantum mechanics (QM) combined with (special) relativity, in particular an upper bound on the propagation velocity of effects, leads naturally to systems with an infinite number of degrees of freedom (relativistic quantum fields).
Philosophy and logic of quantum physics
Dapprich, Jan Philipp
2015-01-01
The book investigates the ontology and logic of quantum physics. The first part discusses the relationship of theory and observation and different views on the ontological status of scientific theories. It introduces the fundamentals of quantum mechanics and some of its interpretations and their compatibility with various ontological positions. In the second part, implications of quantum mechanics on classical logic, especially on the distributive law and bivalence, as discussed by Garrett Birkhoff & John von Neumann (1936) and Hilary Putnam (1968), and their counterarguments are reconstructed and discussed. It is concluded that classical logic is sufficient for dealing with quantum mechanical propositions.
REDUCE in elementary particle physics. Quantum electrodynamics
International Nuclear Information System (INIS)
Grozin, A.G.
1990-01-01
This preprint is the second part of the problem book on using REDUCE for calculations of cross sections and decay probabilities in elementary particle physics. It contains examples of calculations in quantum electrodynamics. 5 refs
Relativistic nuclear physics and quantum chromodynamics. Abstracts
International Nuclear Information System (INIS)
1994-01-01
The data of investigations on problems of high energy physics are given. Special attention pays to quantum chromodynamics at large distances, cumulative processes, multiquark states and relativistic nuclear collisions
Physics: Quantum problems solved through games
Maniscalco, Sabrina
2016-04-01
Humans are better than computers at performing certain tasks because of their intuition and superior visual processing. Video games are now being used to channel these abilities to solve problems in quantum physics. See Letter p.210
Quantum Mechanics as Classical Physics
Sebens, CT
2015-01-01
Here I explore a novel no-collapse interpretation of quantum mechanics which combines aspects of two familiar and well-developed alternatives, Bohmian mechanics and the many-worlds interpretation. Despite reproducing the empirical predictions of quantum mechanics, the theory looks surprisingly classical. All there is at the fundamental level are particles interacting via Newtonian forces. There is no wave function. However, there are many worlds.
Quantum effects in accelerator physics
International Nuclear Information System (INIS)
Leinaas, J.M.
1991-08-01
Quantum effects for electrons in a storage ring are discussed, in particular the polarization effect due to spin flip synchrotron radiation. The electrons are treated as a simple quantum mechnical two-level system coupled to the orbital motion and the radiation field. The excitations of the spin system are then related to the Unruh effect, i.e. the effect that an accelerated radiation detector is thermally excited by vacuum fluctuations. 24 refs., 2 figs
Quantum Entropy and Its Applications to Quantum Communication and Statistical Physics
Directory of Open Access Journals (Sweden)
Masanori Ohya
2010-05-01
Full Text Available Quantum entropy is a fundamental concept for quantum information recently developed in various directions. We will review the mathematical aspects of quantum entropy (entropies and discuss some applications to quantum communication, statistical physics. All topics taken here are somehow related to the quantum entropy that the present authors have been studied. Many other fields recently developed in quantum information theory, such as quantum algorithm, quantum teleportation, quantum cryptography, etc., are totally discussed in the book (reference number 60.
The quantum world philosophical debates on quantum physics
Zwirn, Hervé
2017-01-01
In this largely nontechnical book, eminent physicists and philosophers address the philosophical impact of recent advances in quantum physics. These are shown to shed new light on profound questions about realism, determinism, causality or locality. The participants contribute in the spirit of an open and honest discussion, reminiscent of the time when science and philosophy were inseparable. After the editors’ introduction, the next chapter reveals the strangeness of quantum mechanics and the subsequent discussions examine our notion of reality. The spotlight is then turned to the topic of decoherence. Bohm’s theory is critically examined in two chapters, and the relational interpretation of quantum mechanics is likewise described and discussed. The penultimate chapter presents a proposal for resolving the measurement problem, and finally the topic of loop quantum gravity is presented by one of its founding fathers, Carlo Rovelli. The original presentations and discussions on which this volume is based t...
Quantum enigma physics encounters consciousness
Rosenblum, Bruce
2012-01-01
Everyone knows that sub-atomic particles have some very strange qualities. Light sometimes behaves like a particle, sometimes like a wave. Objects separated by vast distances interact faster than the speed of light what Einstein called spooky action at a distance'. Most strangely, the behaviour of objects somehow seems to be determined in retrospect, depending on what the observer is looking for. In this ground-breaking work the authors show how these quantum properties are being observed in larger and larger objects. They set out carefully and cautiously exactly what quantum theory
Elements of classical and quantum physics
Cini, Michele
2018-01-01
This book presents the basic elements of theoretical physics in a highly accessible, captivating way for university students in the third year of a degree in physics. It covers analytical mechanics, thermodynamics and statistical physics, special and general relativity and non-relativistic quantum theory, fully developing the necessary mathematical methods beyond standard calculus. The central theme is scientific curiosity and the main focus is on the experimental meaning of all quantities and equations. Several recent verifications of General Relativity are presented, with emphasis on the physical effects – why they were predicted to exist and what signals they were seen to produce. Similarly, the basic reasons why superconductors have zero resistance and are perfect diamagnets are pinpointed. Quantum Eraser Experiments and Delayed Choice Experiments are described. Many statements of Quantum Theory are a challenge to common sense and some crucial predictions have often been considered hard to believe and h...
Quantum physics what everyone needs to know
Raymer, Michael G
2017-01-01
Around 1900, physicists started to discover particles like electrons, protons, and neutrons, and with these discoveries believed they could predict the internal behavior of the atom. However, once their predictions were compared to the results of experiments in the real world, it became clear that the principles of classical physics and mechanics were far from capable of explaining phenomena on the atomic scale. With this realization came the advent of quantum physics, one of the most important intellectual movements in human history. Today, quantum physics is everywhere: it explains how our computers work, how lasers transmit information across the Internet, and allows scientists to predict accurately the behavior of nearly every particle in nature. Its application continues to be fundamental in the investigation of the most expansive questions related to our world and the universe. However, while the field and principles of quantum physics are known to have nearly limitless applications, the fundamental rea...
Teaching Quantum Physics without Paradoxes
Hobson, Art
2007-01-01
Although the resolution to the wave-particle paradox has been known for 80 years, it is seldom presented. Briefly, the resolution is that material particles and photons are the quanta of extended spatially continuous but energetically quantized fields. But because the resolution resides in quantum field theory and is not usually spelled out in…
Physical models of semiconductor quantum devices
Fu, Ying
2013-01-01
The science and technology relating to nanostructures continues to receive significant attention for its applications to various fields including microelectronics, nanophotonics, and biotechnology. This book describes the basic quantum mechanical principles underlining this fast developing field. From the fundamental principles of quantum mechanics to nanomaterial properties, from device physics to research and development of new systems, this title is aimed at undergraduates, graduates, postgraduates, and researchers.
Quantum mechanics as total physical theory
International Nuclear Information System (INIS)
Slavnov, D.A.
2002-01-01
It is shown that the principles of the total physical theory and conclusions of the standard quantum mechanics are not at such an antagonistic variance as it is usually accepted. The axioms, which make it possible to plot the renewed mathematical scheme of the quantum mechanics are formulated within the frames of the algebraic approach. The above scheme includes the standard mathematical apparatus of the quantum mechanics. Simultaneously there exists the mathematical object, which adequately describes the individual experiment. The examples of applying the proposed scheme is presented [ru
Nonlinear aspects of quantum plasma physics
International Nuclear Information System (INIS)
Shukla, Padma K; Eliasson, B
2010-01-01
Dense quantum plasmas are ubiquitous in planetary interiors and in compact astrophysical objects (e.g., the interior of white dwarf stars, in magnetars, etc.), in semiconductors and micromechanical systems, as well as in the next-generation intense laser-solid density plasma interaction experiments and in quantum X-ray free-electron lasers. In contrast to classical plasmas, quantum plasmas have extremely high plasma number densities and low temperatures. Quantum plasmas are composed of electrons, positrons and holes, which are degenerate. Positrons (holes) have the same (slightly different) mass as electrons, but opposite charge. The degenerate charged particles (electrons, positrons, and holes) obey the Fermi-Dirac statistics. In quantum plasmas, there are new forces associated with (i) quantum statistical electron and positron pressures, (ii) electron and positron tunneling through the Bohm potential, and (iii) electron and positron angular momentum spin. Inclusion of these quantum forces allows the existence of very high-frequency dispersive electrostatic and electromagnetic waves (e.g., in the hard X-ray and gamma-ray regimes) with extremely short wavelengths. In this review paper, we present theoretical backgrounds for some important nonlinear aspects of wave-wave and wave-electron interactions in dense quantum plasmas. Specifically, we focus on nonlinear electrostatic electron and ion plasma waves, novel aspects of three-dimensional quantum electron fluid turbulence, as well as nonlinearly coupled intense electromagnetic waves and localized plasma wave structures. Also discussed are the phase-space kinetic structures and mechanisms that can generate quasistationary magnetic fields in dense quantum plasmas. The influence of the external magnetic field and the electron angular momentum spin on the electromagnetic wave dynamics is discussed. Finally, future perspectives of the nonlinear quantum plasma physics are highlighted. (reviews of topical problems)
Strictly contractive quantum channels and physically realizable quantum computers
International Nuclear Information System (INIS)
Raginsky, Maxim
2002-01-01
We study the robustness of quantum computers under the influence of errors modeled by strictly contractive channels. A channel T is defined to be strictly contractive if, for any pair of density operators ρ, σ in its domain, parallel Tρ-Tσ parallel 1 ≤k parallel ρ-σ parallel 1 for some 0≤k 1 denotes the trace norm). In other words, strictly contractive channels render the states of the computer less distinguishable in the sense of quantum detection theory. Starting from the premise that all experimental procedures can be carried out with finite precision, we argue that there exists a physically meaningful connection between strictly contractive channels and errors in physically realizable quantum computers. We show that, in the absence of error correction, sensitivity of quantum memories and computers to strictly contractive errors grows exponentially with storage time and computation time, respectively, and depends only on the constant k and the measurement precision. We prove that strict contractivity rules out the possibility of perfect error correction, and give an argument that approximate error correction, which covers previous work on fault-tolerant quantum computation as a special case, is possible
Development of quantum perspectives in modern physics
Directory of Open Access Journals (Sweden)
Charles Baily
2009-03-01
Full Text Available Introductory undergraduate courses in classical physics stress a perspective that can be characterized as realist; from this perspective, all physical properties of a classical system can be simultaneously specified and thus determined at all future times. Such a perspective can be problematic for introductory quantum physics students, who must develop new perspectives in order to properly interpret what it means to have knowledge of quantum systems. We document this evolution in student thinking in part through pre- and post-instruction evaluations using the Colorado Learning Attitudes about Science Survey. We further characterize variations in student epistemic and ontological commitments by examining responses to two essay questions, coupled with responses to supplemental quantum attitude statements. We find that, after instruction in modern physics, many students are still exhibiting a realist perspective in contexts where a quantum-mechanical perspective is needed. We further find that this effect can be significantly influenced by instruction, where we observe variations for courses with differing learning goals. We also note that students generally do not employ either a realist or a quantum perspective in a consistent manner.
Advanced Level Physics Students' Conceptions of Quantum Physics.
Mashhadi, Azam
This study addresses questions about particle physics that focus on the nature of electrons. Speculations as to whether they are more like particles or waves or like neither illustrate the difficulties with which students are confronted when trying to incorporate the concepts of quantum physics into their overall conceptual framework. Such…
Recent developments in quantum plasma physics
International Nuclear Information System (INIS)
Shukla, P K; Eliasson, B
2010-01-01
We present a review of recent developments in nonlinear quantum plasma physics involving quantum hydrodynamics and effective nonlinear Schroedinger equation formalisms, for describing collective phenomena in dense quantum plasmas with degenerate electrons. As examples, we discuss simulation studies of the formation and dynamics of dark solitons and quantum vortices, and of nonlinear interactions between intense circularly polarized electromagnetic (CPEM) waves and electron plasma oscillations (EPOs) in dense quantum-electron plasmas with immobile ions. The electron dynamics of dark solitons and quantum vortices is governed by a pair of equations comprising the nonlinear Schroedinger and Poisson system of equations. Both dark solitons and singly charged electron vortices are robust, and the latter tend to form pairs of oppositely charged vortices. The two-dimensional quantum-electron vortex pairs survive during collisions under the change of partners. The dynamics of the CPEM waves is governed by a nonlinear Schroedinger equation, which is nonlinearly coupled with the Schroedinger equation of the EPOs via the relativistic ponderomotive force, the relativistic electron mass increase in the CPEM field, and the electron density fluctuations. The present governing equations in one-spatial dimension admit stationary solutions in the form of dark solitons. The nonlinear equations also depict trapping of localized CPEM wave envelopes in the electron density holes that are associated with a positive potential profile.
Quantum Physics and Human Language
Hartle, James B.
2006-01-01
Human languages employ constructions that tacitly assume specific properties of the limited range of phenomena they evolved to describe. These assumed properties are true features of that limited context, but may not be general or precise properties of all the physical situations allowed by fundamental physics. In brief, human languages contain `excess baggage' that must be qualified, discarded, or otherwise reformed to give a clear account in the context of fundamental physics of even the ev...
Quantum photonic network and physical layer security.
Sasaki, Masahide; Endo, Hiroyuki; Fujiwara, Mikio; Kitamura, Mitsuo; Ito, Toshiyuki; Shimizu, Ryosuke; Toyoshima, Morio
2017-08-06
Quantum communication and quantum cryptography are expected to enhance the transmission rate and the security (confidentiality of data transmission), respectively. We study a new scheme which can potentially bridge an intermediate region covered by these two schemes, which is referred to as quantum photonic network. The basic framework is information theoretically secure communications in a free space optical (FSO) wiretap channel, in which an eavesdropper has physically limited access to the main channel between the legitimate sender and receiver. We first review a theoretical framework to quantify the optimal balance of the transmission efficiency and the security level under power constraint and at finite code length. We then present experimental results on channel characterization based on 10 MHz on-off keying transmission in a 7.8 km terrestrial FSO wiretap channel.This article is part of the themed issue 'Quantum technology for the 21st century'. © 2017 The Author(s).
Certified randomness in quantum physics.
Acín, Antonio; Masanes, Lluis
2016-12-07
The concept of randomness plays an important part in many disciplines. On the one hand, the question of whether random processes exist is fundamental for our understanding of nature. On the other, randomness is a resource for cryptography, algorithms and simulations. Standard methods for generating randomness rely on assumptions about the devices that are often not valid in practice. However, quantum technologies enable new methods for generating certified randomness, based on the violation of Bell inequalities. These methods are referred to as device-independent because they do not rely on any modelling of the devices. Here we review efforts to design device-independent randomness generators and the associated challenges.
The challenge of quantum computer simulations of physical phenomena
International Nuclear Information System (INIS)
Ortiz, G.; Knill, E.; Gubernatis, J.E.
2002-01-01
The goal of physics simulation using controllable quantum systems ('physics imitation') is to exploit quantum laws to advantage, and thus accomplish efficient simulation of physical phenomena. In this Note, we discuss the fundamental concepts behind this paradigm of information processing, such as the connection between models of computation and physical systems. The experimental simulation of a toy quantum many-body problem is described
Quantum Well Infrared Photodetectors Physics and Applications
Schneider, Harald
2007-01-01
Addressed to both students as a learning text and scientists/engineers as a reference, this book discusses the physics and applications of quantum-well infrared photodetectors (QWIPs). It is assumed that the reader has a basic background in quantum mechanics, solid-state physics, and semiconductor devices. To make this book as widely accessible as possible, the treatment and presentation of the materials is simple and straightforward. The topics for the book were chosen by the following criteria: they must be well-established and understood; and they should have been, or potentially will be, used in practical applications. The monograph discusses most aspects relevant for the field but omits, at the same time, detailed discussions of specialized topics such as the valence-band quantum wells.
Summer Workshop on Physics, Mathematics, and All That Quantum Jazz
Bando, Masamitsu; Güngördü, Utkan; Physics, Mathematics, and All That Quantum Jazz
2014-01-01
This book is a collection of contributions from a Summer Workshop on Physics, Mathematics, and All That Quantum Jazz . Subjects of the symposium include quantum information theory, quantum annealing, Bose gases, and thermodynamics from a viewpoint of quantum physics. Contributions to this book are prepared in a self-contained manner so that readers with a modest background may understand the subjects.
Embedded random matrix ensembles in quantum physics
Kota, V K B
2014-01-01
Although used with increasing frequency in many branches of physics, random matrix ensembles are not always sufficiently specific to account for important features of the physical system at hand. One refinement which retains the basic stochastic approach but allows for such features consists in the use of embedded ensembles. The present text is an exhaustive introduction to and survey of this important field. Starting with an easy-to-read introduction to general random matrix theory, the text then develops the necessary concepts from the beginning, accompanying the reader to the frontiers of present-day research. With some notable exceptions, to date these ensembles have primarily been applied in nuclear spectroscopy. A characteristic example is the use of a random two-body interaction in the framework of the nuclear shell model. Yet, topics in atomic physics, mesoscopic physics, quantum information science and statistical mechanics of isolated finite quantum systems can also be addressed using these ensemb...
Making Introductory Quantum Physics Understandable and Interesting
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 1. Making Introductory Quantum Physics Understandable and Interesting. Ranjana Y Abhang. Classroom Volume 10 Issue 1 January 2005 pp 63-73. Fulltext. Click here to view fulltext PDF. Permanent link:
Parables of Physics and a Quantum Romance
Machacek, A. C.
2014-01-01
Teachers regularly use stories to amplify the concepts taught and to encourage student engagement. The literary form of a parable is particularly suitable for classroom use, and examples are given, including a longer one intended to stimulate discussion on the nature of quantum physics (and the wave-particle duality in particular).
Mathematics of classical and quantum physics
Byron, Frederick W
Well-organized text designed to complement graduate-level physics texts in classical mechanics, electricity, magnetism, and quantum mechanics. Topics include theory of vector spaces, analytic function theory, Green's function method of solving differential and partial differential equations, theory of groups, more. Many problems, suggestions for further reading.
Scholar-activating instructional materials on quantum physics. Pt. 1. On the way to quantum physics
International Nuclear Information System (INIS)
Huebel, Horst
2008-01-01
Traditionally in the interest on quantum physics referring to school the question holds the spotlight, whether electrons of photons are now particles ore waves, a formulation of the question, which is often characterized by the phrase ''Wave-particle dualism'', which as is known not exists in its original meaning. Contrarily by the author - starting from important preparations of Kueblbeck and Mueller - a new concept for the treatment of quantum physics for the school is proposed, which puts fundamental facts in the foreground, comparable with Kueblbeck-Mueller's ''Wesenzuege''. The fundamental facts are similar to axioms of quantum physics, by means of which a large number of experiments and phenomena of quantum physics can at least qualitatively - in a heuristic way - be explained. Instead of the mentioned wave-particle dualism here undeterminism and complementarity are put in the foreground. The new concept is in the internet extensively presented under http://www.forphys.de with may further materials. In the partial volumes of this publication manifold and carefully elaborated instructional materials are presented, by which the scholars can themselves elaborate the partial set of quantum physics referred to school by different methods like learning at stations, short referates, internet research, group puzzle, the query-sheet or the card-index method etc. In the present 1. part materials for prestages of quantum physics are provided, so to interference trials, which-way experiments, trials on the particle conception of quantum theory, on photons, and on Planck's action quantum. A section is also dedicated to the so-called ''model-philosophy'' as preliminary interpretation of quantum physics, which corresponds more to tradiational ways of proceeding
Finite quantum physics and noncommutative geometry
International Nuclear Information System (INIS)
Balachandran, A.P.; Ercolessi, E.; Landi, G.; Teotonio-Sobrinho, P.; Lizzi, F.; Sparano, G.
1994-04-01
Conventional discrete approximations of a manifold do not preserve its nontrivial topological features. In this article we describe an approximation scheme due to Sorkin which reproduces physically important aspects of manifold topology with striking fidelity. The approximating topological spaces in this scheme are partially ordered sets (posets). Now, in ordinary quantum physics on a manifold M, continuous probability densities generate the commutative C * -algebra C(M) of continuous functions on M. It has a fundamental physical significance, containing the information to reconstruct the topology of M, and serving to specify the domains of observables like the Hamiltonian. For a poset, the role of this algebra is assumed by a noncommutative C * -algebra A. As noncommutative geometries are based on noncommutative C * -algebra, we therefore have a remarkable connection between finite approximations to quantum physics and noncommutative geometries. Varies methods for doing quantum physics using A are explored. Particular attention is paid to developing numerically viable approximation schemes which at the same time preserve important topological features of continuum physics. (author). 21 refs, 13 figs
Quantum physics reimagined for the general public
Bobroff, Julien
2015-03-01
Quantum Physics has always been a challenging issue for outreach. It is invisible, non-intuitive and written in sophisticated mathematics. In our ``Physics Reimagined'' research group, we explore new ways to present that field to the general public. Our approach is to develop close collaborations between physicists and designers or graphic artists. By developing this new kind of dialogue, we seek to find new ways to present complex phenomena and recent research topics to the public at large. For example, we created with web-illustrators a series of 3D animations about basic quantum laws and research topics (graphene, Bose-Einstein condensation, decoherence, pump-probe techniques, ARPES...). We collaborated with designers to develop original setups, from quantum wave animated models or foldings to a superconducting circus with levitating animals. With illustrators, we produced exhibits, comic strips or postcards displaying the physicists in their labs, either famous ones or even our own colleagues in their daily life as researchers. With artists, we recently made a stop-motion picture to explain in an esthetic way the process of discovery and scientific publication. We will discuss how these new types of outreach projects allowed us to engage the public with modern physics both on a scientific and cultural level and how the concepts and process can easily be replicated and expanded by other physicists. We are at the precise time when creative tools, interfaces, and ways of sharing and learning are rapidly evolving (wikipedia, MOOCs, smartphones...). If scientists don't step forward to employ these tools and develop new resources, other people will, and the integrity of the science and underlying character of research risks being compromised. All our productions are free to use and can be downloaded at www.PhysicsReimagined.com (for 3D quantum videos, specific link: www.QuantumMadeSimple.com) This work benefited from the support of the Chair ``Physics Reimagined
Nuclear physics, symmetries, and quantum chaos
International Nuclear Information System (INIS)
Bunakov, V.E.
1999-01-01
The reasons why the problem of chaos is of great topical interest in modern physics are briefly summarized, and it is indicated that ambiguities in the concept of quantum chaos present the greatest difficulties in these realms. The theory of random matrices and strength functions are generalized to demonstrate that chaotization of a system is associated with the violation of its symmetries. A criterion of quantum chaoticity is formulated in terms of the spreading width Γ spr . In the classical limit, this criterion reduces to Lyapunov's stability criteria. It is shown that the proposed criterion is applicable to standard problems of the modern theory of dynamical chaos
Quantum electronics for atomic physics and telecommunication
Nagourney, Warren G
2014-01-01
Nagourney provides a course in quantum electronics for researchers in atomic physics and other related areas (including telecommunications). The book covers the usual topics, such as Gaussian beams, optical cavities, lasers, non-linear optics, modulation techniques and fibre optics, but also includes a number of areas not usually found in a textbook on quantum electronics, such as the enhancement of non-linear processes in a build-up cavity or periodically poled waveguide, impedance matching into a cavity and astigmatism in ring cavities.
Quantum Gravity (Cambridge Monographs on Mathematical Physics)
International Nuclear Information System (INIS)
Kiefer, C
2005-01-01
The most difficult unsolved problem in fundamental theoretical physics is the consistent implementation of the gravitational interaction into a quantum framework, which would lead to a theory of quantum gravity. Although a final answer is still pending, several promising attempts do exist. Despite the general title, this book is about one of them - loop quantum gravity. This approach proceeds from the idea that a direct quantization of Einstein's theory of general relativity is possible. In contrast to string theory, it presupposes that the unification of all interactions is not needed as a prerequisite for quantum gravity. Usually one divides theories of quantum general relativity into covariant and canonical approaches. Covariant theories employ four-dimensional concepts in its formulation, one example being the path integral approach. Canonical theories start from a classical Hamiltonian version of the theory in which spacetime is foliated into spacelike hypersurfaces. Loop quantum gravity is a variant of the canonical approach, the oldest being quantum geometrodynamics where the fundamental configuration variable is the three-metric. Loop quantum gravity has developed from a new choice of canonical variables introduced by Abhay Ashtekar in 1986, the new configuration variable being a connection defined on a three-manifold. Instead of the connection itself, the loop approach employs a non-local version in which the connection is integrated over closed loops. This is similar to the Wilson loops used in gauge theories. Carlo Rovelli is one of the pioneers of loop quantum gravity which he started to develop with Lee Smolin in two papers written in 1988 and 1990. In his book, he presents a comprehensive and competent overview of this approach and provides at the same time the necessary technical background in order to make the treatment self-contained. In fact, half of the book is devoted to 'preparations' giving a detailed account of Hamiltonian mechanics, quantum
Theoretical physics 6 quantum mechanics : basics
Nolting, Wolfgang
2017-01-01
This textbook offers a clear and comprehensive introduction to the basics of quantum mechanics, one of the core components of undergraduate physics courses. It follows on naturally from the previous volumes in this series, thus developing the physical understanding further on to quantized states. The first part of the book introduces wave equations while exploring the Schrödinger equation and the hydrogen atom. More complex themes are covered in the second part of the book, which describes the Dirac formulism of quantum mechanics. Ideally suited to undergraduate students with some grounding in classical mechanics and electrodynamics, the book is enhanced throughout with learning features such as boxed inserts and chapter summaries, with key mathematical derivations highlighted to aid understanding. The text is supported by numerous worked examples and end of chapter problem sets. About the Theoretical Physics series Translated from the renowned and highly successful German editions, the eight volumes of this...
Physics of strained quantum well lasers
Loehr, John P
1998-01-01
When this publisher offered me the opportunity to \\\\Tite a book, some six years ago, I did not hesitate to say yes. I had just spent the last four years of graduate school struggling to understand the physics of strained quantum well lasers, and it seemed to me the whole experience was much more difficult that it should have been. For although many of the results I needed were easy to locate, the underlying physical premises and intervening steps were not. If only I had a book providing the derivations, I could have absorbed them and gone on my way. Such a book lies before you. It provides a unified and self-contained descrip tion of the essential physics of strained quantum well lasers, starting from first principles whenever feasible. The presentation I have chosen requires only the standard introductory background in quantum mechanics, solid state physics, and electromagnetics expected of entering graduate students in physics or elec trical engineering. A single undergraduate course in each of these su...
Sources and evolution of quantum physics
International Nuclear Information System (INIS)
Escoubes, B.
2005-01-01
The author has gathered in this book the founder articles of fundamental physics to illustrate the way how physics'ideas and concepts have emerged to form the modern physics we know today. The book is divided into 6 chapters: 1) from the Greek idea of matter to the discovery of radioactivity, 2) from relativity to quantification, 3) the devising of quantum mechanics, 4) from relativistic quantum mechanics to quantum field theory, 5) the great moments of particle physics, and 6) towards the great unification. 19 articles have been selected to illustrate the milestones of physics. Most are reproduced in full in their original texts. Among them we can find the article of Einstein about the existence of the photon, or the article of Pauli in which the exclusion principle is drafted or the article of Yukawa about the existence of the meson. The theoretical advances proposed in the articles are highlighted and put into perspective in discerning commentaries set in the different chapters. (A.C.)
Artificial Atoms: from Quantum Physics to Applications
International Nuclear Information System (INIS)
2014-01-01
The primary objective of this workshop is to survey the most recent advances of technologies enabling single atom- and artificial atom-based devices. These include the assembly of artificial molecular structures with magnetic dipole and optical interactions between engineered atoms embedded in solid-state lattices. The ability to control single atoms in diamond or similar solids under ambient operating conditions opens new perspectives for technologies based on nanoelectronics and nanophotonics. The scope of the workshop is extended towards the physics of strong coupling between atoms and radiation field modes. Beyond the traditional atom-cavity systems, artificial dipoles coupled to microwave radiation in circuit quantum electrodynamics is considered. All these technologies mutually influence each other in developing novel devices for sensing at the quantum level and for quantum information processing.
Discovery Mondays: Quantum physics - incredible but true
2006-01-01
Physicists use two main theories to describe the world around us - the general theory of relativity to describe the infinitely large and quantum theory to describe the infinitesimally small, at the scale of the atom and its constituent parts. Quantum physics is as fascinating as it is bewildering. And yet it's used in many practical applications - medical imaging, lasers and computers, to name but a few. Over the course of the evening, you'll become acquainted with strange phenomena such as super-fluidity, teleportation and quantum cryptography. And through some amazing sleights-of-hand and experiments, you'll be taken on a journey into the mysteries of the infinitesimally small... The event will be conducted in French. Come to Microcosm, (Reception Building 33, Meyrin site), on Monday 3 July from 7.30 p.m. to 9.00 p.m. Entrance is free http://www.cern.ch/LundisDecouverte/
Nonrelativistic quantum X-ray physics
Hau-Riege, Stefan P
2015-01-01
Providing a solid theoretical background in photon-matter interaction, Nonrelativistic Quantum X-Ray Physics enables readers to understand experiments performed at XFEL-facilities and x-ray synchrotrons. As a result, after reading this book, scientists and students will be able to outline and perform calculations of some important x-ray-matter interaction processes. Key features of the contents are that the scope reaches beyond the dipole approximation when necessary and that it includes short-pulse interactions. To aid the reader in this transition, some relevant examples are discussed in detail, while non-relativistic quantum electrodynamics help readers to obtain an in-depth understanding of the formalisms and processes. The text presupposes a basic (undergraduate-level) understanding of mechanics, electrodynamics, and quantum mechanics. However, more specialized concepts in these fields are introduced and the reader is directed to appropriate references. While primarily benefiting users of x-ray light-sou...
Quantum mechanics and the physical reality concept
International Nuclear Information System (INIS)
von Borzeszkowski, H.H.; Wahsner, R.
1988-01-01
The difference between the measurement bases of classical and quantum mechanics is often interpreted as a loss of reality arising in quantum mechanics. In this paper it is shown that this apparent loss occurs only if one believes that refined everyday experience determines the Euclidean space as the real space, instead of considering this space, both in classical and quantum mechanics, as a theoretical construction needed for measurement and representing one part of a dualistic space conception. From this point of view, Einstein's program of a unified field theory can be interpreted as the attempt to find a physical theory that is less dualistic. However, if one regards this dualism as resulting from the requirements of measurements, one can hope for a weakening of the dualism but not expect to remove it completely
Quantum algorithms for computational nuclear physics
Directory of Open Access Journals (Sweden)
Višňák Jakub
2015-01-01
Full Text Available While quantum algorithms have been studied as an efficient tool for the stationary state energy determination in the case of molecular quantum systems, no similar study for analogical problems in computational nuclear physics (computation of energy levels of nuclei from empirical nucleon-nucleon or quark-quark potentials have been realized yet. Although the difference between the above mentioned studies might seem negligible, it will be examined. First steps towards a particular simulation (on classical computer of the Iterative Phase Estimation Algorithm for deuterium and tritium nuclei energy level computation will be carried out with the aim to prove algorithm feasibility (and extensibility to heavier nuclei for its possible practical realization on a real quantum computer.
Towards testing quantum physics in deep space
Kaltenbaek, Rainer
2016-07-01
MAQRO is a proposal for a medium-sized space mission to use the unique environment of deep space in combination with novel developments in space technology and quantum technology to test the foundations of physics. The goal is to perform matter-wave interferometry with dielectric particles of up to 10^{11} atomic mass units and testing for deviations from the predictions of quantum theory. Novel techniques from quantum optomechanics with optically trapped particles are to be used for preparing the test particles for these experiments. The core elements of the instrument are placed outside the spacecraft and insulated from the hot spacecraft via multiple thermal shields allowing to achieve cryogenic temperatures via passive cooling and ultra-high vacuum levels by venting to deep space. In combination with low force-noise microthrusters and inertial sensors, this allows realizing an environment well suited for long coherence times of macroscopic quantum superpositions and long integration times. Since the original proposal in 2010, significant progress has been made in terms of technology development and in refining the instrument design. Based on these new developments, we submitted/will submit updated versions of the MAQRO proposal in 2015 and 2016 in response to Cosmic-Vision calls of ESA for a medium-sized mission. A central goal has been to address and overcome potentially critical issues regarding the readiness of core technologies and to provide realistic concepts for further technology development. We present the progress on the road towards realizing this ground-breaking mission harnessing deep space in novel ways for testing the foundations of physics, a technology pathfinder for macroscopic quantum technology and quantum optomechanics in space.
Green's functions in quantum physics
Economou, Eleftherios N
2006-01-01
The main part of this book is devoted to the simplest kind of Green's functions, namely the solutions of linear differential equations with a -function source. It is shown that these familiar Green's functions are a powerful tool for obtaining relatively simple and general solutions of basic problems such as scattering and bound-level information. The bound-level treatment gives a clear physical understanding of "difficult" questions such as superconductivity, the Kondo effect, and, to a lesser degree, disorder-induced localization. The more advanced subject of many-body Green's functions is presented in the last part of the book.
Quantum mechanical tunneling in chemical physics
Nakamura, Hiroki
2016-01-01
Quantum mechanical tunneling plays important roles in a wide range of natural sciences, from nuclear and solid-state physics to proton transfer and chemical reactions in chemistry and biology. Responding to the need for further understanding of multidimensional tunneling, the authors have recently developed practical methods that can be applied to multidimensional systems. Quantum Mechanical Tunneling in Chemical Physics presents basic theories, as well as original ones developed by the authors. It also provides methodologies and numerical applications to real molecular systems. The book offers information so readers can understand the basic concepts and dynamics of multidimensional tunneling phenomena and use the described methods for various molecular spectroscopy and chemical dynamics problems. The text focuses on three tunneling phenomena: (1) energy splitting, or tunneling splitting, in symmetric double well potential, (2) decay of metastable state through tunneling, and (3) tunneling effects in chemical...
Qigong meets quantum physics experiencing cosmic oneness
Bock-Möbius, Imke
2012-01-01
Quantum physicists have reached a point commonly only attained by mystics: they understand something with amazing clarity yet can only talk about it in parables and metaphors. In this context, qigong with its Daoist background is a powerful way to integrate these apparently opposing ways of apperception and understanding. It allows us to realise cosmic oneness in the activities of daily life. This book succeeds in presenting both an easily accessible outline of quantum physics and also an appreciation of mysticism beyond vagueness and obscurity. From here it describes the physical and mental movements of qigong as a way of integrating body and mind, head and heart, detailing specific exercises and outlining their rationale and effects.
Relativity and quantum physics for beginners
Manly, Steven L
2009-01-01
As we humans have expanded our horizons to see things vastly smaller, faster, larger, and farther than ever before, we have been forced to confront preconceptions born of the human experience and create wholly new ways of looking at the world around us. The theories of relativity and quantum physics were developed out of this need and have provided us with phenomenal, mind-twisting insights into the strange and exciting reality show of our universe.Relativity and Quantum Physics For Beginners is an entertaining and accessible introduction to the bizarre concepts that fueled the scientific revolution of the 20th century and led to amazing advances in our understanding of the universe.
Meaning of counterfactual statements in quantum physics
International Nuclear Information System (INIS)
Stapp, H.P.
1998-01-01
David Mermin suggests that my recent proof pertaining to quantum nonlocality is undermined by an essential ambiguity pertaining to the meaning of counterfactual statements in quantum physics. The ambiguity he cites arises from his imposition of a certain criterion for the meaningfulness of such counterfactual statements. That criterion conflates the meaning of a counterfactual statement with the details of a proof of its validity in such a way as to make the meaning of such a statement dependent upon the context in which it occurs. That dependence violates the normal demand in logic that the meaning of a statement be defined by the words in the statement itself, not by the context in which the statement occurs. My proof conforms to that normal requirement. I describe the context-independent meaning within my proof of the counterfactual statements in question. copyright 1998 American Association of Physics Teachers
EPR paradox, quantum nonlocality and physical reality
International Nuclear Information System (INIS)
Kupczynski, M
2016-01-01
Eighty years ago Einstein, Podolsky and Rosen demonstrated that instantaneous reduction of wave function, believed to describe completely a pair of entangled physical systems, led to EPR paradox. The paradox disappears in statistical interpretation of quantum mechanics (QM) according to which a wave function describes only an ensemble of identically prepared physical systems. QM predicts strong correlations between outcomes of measurements performed on different members of EPR pairs in far-away locations. Searching for an intuitive explanation of these correlations John Bell analysed so called local realistic hidden variable models and proved that correlations consistent with these models satisfy Bell inequalities which are violated by some predictions of QM and by experimental data. Several different local models were constructed and inequalities proven. Some eminent physicists concluded that Nature is definitely nonlocal and that it is acting according to a law of nonlocal randomness. According to these law perfectly random, but strongly correlated events, can be produced at the same time in far away locations and a local and causal explanation of their occurrence cannot be given. We strongly disagree with this conclusion and we prove the contrary by analysing in detail some influential finite sample proofs of Bell and CHSH inequalities and so called Quantum Randi Challenges. We also show how one can win so called Bell's game without violating locality of Nature. Nonlocal randomness is inconsistent with local quantum field theory, with standard model in elementary particle physics and with causal laws and adaptive dynamics prevailing in the surrounding us world. The experimental violation of Bell-type inequalities does not prove the nonlocality of Nature but it only confirms a contextual character of quantum observables and gives a strong argument against counterfactual definiteness and against a point of view according to which experimental outcomes are
EPR paradox, quantum nonlocality and physical reality
Kupczynski, M.
2016-03-01
Eighty years ago Einstein, Podolsky and Rosen demonstrated that instantaneous reduction of wave function, believed to describe completely a pair of entangled physical systems, led to EPR paradox. The paradox disappears in statistical interpretation of quantum mechanics (QM) according to which a wave function describes only an ensemble of identically prepared physical systems. QM predicts strong correlations between outcomes of measurements performed on different members of EPR pairs in far-away locations. Searching for an intuitive explanation of these correlations John Bell analysed so called local realistic hidden variable models and proved that correlations consistent with these models satisfy Bell inequalities which are violated by some predictions of QM and by experimental data. Several different local models were constructed and inequalities proven. Some eminent physicists concluded that Nature is definitely nonlocal and that it is acting according to a law of nonlocal randomness. According to these law perfectly random, but strongly correlated events, can be produced at the same time in far away locations and a local and causal explanation of their occurrence cannot be given. We strongly disagree with this conclusion and we prove the contrary by analysing in detail some influential finite sample proofs of Bell and CHSH inequalities and so called Quantum Randi Challenges. We also show how one can win so called Bell's game without violating locality of Nature. Nonlocal randomness is inconsistent with local quantum field theory, with standard model in elementary particle physics and with causal laws and adaptive dynamics prevailing in the surrounding us world. The experimental violation of Bell-type inequalities does not prove the nonlocality of Nature but it only confirms a contextual character of quantum observables and gives a strong argument against counterfactual definiteness and against a point of view according to which experimental outcomes are produced
Teaching Quantum Physics in Upper Secondary School in France:
Lautesse, Philippe; Vila Valls, Adrien; Ferlin, Fabrice; Héraud, Jean-Loup; Chabot, Hugues
2015-01-01
One of the main problems in trying to understand quantum physics is the nature of the referent of quantum theory. This point is addressed in the official French curriculum in upper secondary school. Starting in 2012, after about 20 years of absence, quantum physics has returned to the national program. On the basis of the historical construction…
Quantum physics of atoms, molecules, solids, nuclei and particles
International Nuclear Information System (INIS)
Eisberg, R.M.; Resnick, R.
1983-01-01
This textbook is intended to be used for students who have been through substantial treatments of elementary differential and integral calculus and elementary level of classical physics. Various phenomena of early quantum physics, basic core of quantum mechanics and its application to one and two-electron atoms, multielectron atoms, quantum statistics and nuclei are discussed
Physics of Quantum Structures in Photovoltaic Devices
Raffaelle, Ryne P.; Andersen, John D.
2005-01-01
There has been considerable activity recently regarding the possibilities of using various nanostructures and nanomaterials to improve photovoltaic conversion of solar energy. Recent theoretical results indicate that dramatic improvements in device efficiency may be attainable through the use of three-dimensional arrays of zero-dimensional conductors (i.e., quantum dots) in an ordinary p-i-n solar cell structure. Quantum dots and other nanostructured materials may also prove to have some benefits in terms of temperature coefficients and radiation degradation associated with space solar cells. Two-dimensional semiconductor superlattices have already demonstrated some advantages in this regard. It has also recently been demonstrated that semiconducting quantum dots can also be used to improve conversion efficiencies in polymeric thin film solar cells. Improvement in thin film cells utilizing conjugated polymers has also be achieved through the use of one-dimensional quantum structures such as carbon nanotubes. It is believed that carbon nanotubes may contribute to both the disassociation as well as the carrier transport in the conjugated polymers used in certain thin film photovoltaic cells. In this paper we will review the underlying physics governing some of the new photovoltaic nanostructures being pursued, as well as the the current methods being employed to produce III-V, II-VI, and even chalcopyrite-based nanomaterials and nanostructures for solar cells.
Integration of classical and quantum physics
International Nuclear Information System (INIS)
Tisza, L.
1989-01-01
The perennial aspect of the Newtonian foundation of mathematical physics is that the concept of ''motion,'' that is, ''kinematics,'' is to serve as the interface between mathematics and physics. Kinematics subdivides into the theory of orbital translation and that of undulation and spinning. Newtonian mechanics is based on giving to translational kinematics a priority over the other modes, since planetary revolution can be represented as translation modified by gravitation. The so-called breakdown of classical physics stems from giving the translational priority a canonical status and extending it to the constituents of matter. We claim that in this case the priority is to be reversed. The main content of this paper is to establish the algebraic model for an indivisible, undulating entity that we call a ''wave simplex.'' It is used as the point of departure for a non-Newtonian quantum dynamics in which physical and algebraic concepts are in close correspondence. The postulates of the classical phenomenological theories and those of the canonical theories based on translational priority are established as theorems under the proper limiting conditions, and forces are constructed rather than postulated. While the formal structure of two-level quantum mechanics is established as well, exception is taken to treating spin as a property of a point particle. It is considered self-evident that a spinning object is orientable, a property accounted for in terms of a unitary triplet. This is the point of departure for an intrinsic particle dynamics. A main result is the integration of classical and quantum physics, thus closing the gap created by the heuristic method of canonical quantization
On the physical realizability of quantum stochastic walks
Taketani, Bruno; Govia, Luke; Schuhmacher, Peter; Wilhelm, Frank
Quantum walks are a promising framework that can be used to both understand and implement quantum information processing tasks. The recently developed quantum stochastic walk combines the concepts of a quantum walk and a classical random walk through open system evolution of a quantum system, and have been shown to have applications in as far reaching fields as artificial intelligence. However, nature puts significant constraints on the kind of open system evolutions that can be realized in a physical experiment. In this work, we discuss the restrictions on the allowed open system evolution, and the physical assumptions underpinning them. We then introduce a way to circumvent some of these restrictions, and simulate a more general quantum stochastic walk on a quantum computer, using a technique we call quantum trajectories on a quantum computer. We finally describe a circuit QED approach to implement discrete time quantum stochastic walks.
Baily, Charles; Finkelstein, Noah D.
2015-01-01
Most introductory quantum physics instructors would agree that transitioning students from classical to quantum thinking is an important learning goal, but may disagree on whether or how this can be accomplished. Although (and perhaps because) physicists have long debated the physical interpretation of quantum theory, many instructors choose to…
The Physics of Quantum Well Infrared Photodetectors
Choi, K K
1999-01-01
In the past, infrared imaging has been used exclusively for military applications. In fact, it can also be useful in a wide range of scientific and commercial applications. However, its wide spread use was impeded by the scarcity of the imaging systems and its high cost. Recently, there is an emerging infrared technology based on quantum well intersubband transition in III-V compound semiconductors. With the new technology, these impedances can be eliminated and a new era of infrared imaging is in sight. This book is designed to give a systematic description on the underlying physics of the ne
Physical properties of the chiral quantum baryon
International Nuclear Information System (INIS)
Mignaco, A.J.; Wulck, S.
1989-01-01
It is presented an account to understand the quantum chiral baryon, which a stable chiral soliton with baryon number one obtained after first quantization by collective coordinates. Starting from the exact series solution to the non-linear sigma model with the hedge-hog configuration, the values of several physical quantities (mass, axial weak coupling, gyromagnetic ratios and radii) as a function of the order of Pade approximants used as approximanted representations of the solution, are calculated. It turns out that consistent results may be obtained, but a better approximation should be developed. (author) [pt
BOOK REVIEW: Quantum Physics in One Dimension
Logan, David
2004-05-01
To a casual ostrich the world of quantum physics in one dimension may sound a little one-dimensional, suitable perhaps for those with an unhealthy obsession for the esoteric. Nothing of course could be further from the truth. The field is remarkably rich and broad, and for more than fifty years has thrown up innumerable challenges. Theorists, realising that the role of interactions in 1D is special and that well known paradigms of higher dimensions (Fermi liquid theory for example) no longer apply, took up the challenge of developing new concepts and techniques to understand the undoubted pecularities of one-dimensional systems. And experimentalists have succeeded in turning pipe dreams into reality, producing an impressive and ever increasing array of experimental realizations of 1D systems, from the molecular to the mesoscopic---spin and ladder compounds, organic superconductors, carbon nanotubes, quantum wires, Josephson junction arrays and so on. Many books on the theory of one-dimensional systems are however written by experts for experts, and tend as such to leave the non-specialist a touch bewildered. This is understandable on both fronts, for the underlying theoretical techniques are unquestionably sophisticated and not usually part of standard courses in many-body theory. A brave author it is then who aims to produce a well rounded, if necessarily partial, overview of quantum physics in one dimension, accessible to a beginner yet taking them to the edge of current research, and providing en route a thorough grounding in the fundamental ideas, basic methods and essential phenomenology of the field. It is of course the brave who succeed in this world, and Thierry Giamarchi does just that with this excellent book, written by an expert for the uninitiated. Aimed in particular at graduate students in theoretical condensed matter physics, and assumimg little theoretical background on the part of the reader (well just a little), Giamarchi writes in a refreshingly
Delgado, Francisco
2017-12-01
Quantum information processing should be generated through control of quantum evolution for physical systems being used as resources, such as superconducting circuits, spinspin couplings in ions and artificial anyons in electronic gases. They have a quantum dynamics which should be translated into more natural languages for quantum information processing. On this terrain, this language should let to establish manipulation operations on the associated quantum information states as classical information processing does. This work shows how a kind of processing operations can be settled and implemented for quantum states design and quantum processing for systems fulfilling a SU(2) reduction in their dynamics.
Quantum physics for dummies. 2. rev. and enl. ed.
International Nuclear Information System (INIS)
Holzner, Steven
2012-01-01
Quantum physics is a central and fascinating, albeit unpopular by many students theme of physics. Steven Holzner explains understandably and alively, what must be known about quantum physics. He explains the foundations of angular momentum and spin, gives tips how complex equations can be solved. Thereby he works with examples, which he explains extensively.
Designing Learning Environments to Teach Interactive Quantum Physics
Puente, Sonia M. Gomez; Swagten, Henk J. M.
2012-01-01
This study aims at describing and analysing systematically an interactive learning environment designed to teach Quantum Physics, a second-year physics course. The instructional design of Quantum Physics is a combination of interactive lectures (using audience response systems), tutorials and self-study in unit blocks, carried out with small…
Designing learning environments to teach interactive Quantum Physics
Gómez Puente, S.M.; Swagten, H.J.M.
2012-01-01
This study aims at describing and analysing systematically an interactive learning environment designed to teach Quantum Physics, a second-year physics course. The instructional design of Quantum Physics is a combination of interactive lectures (using audience response systems), tutorials and
Refined Characterization of Student Perspectives on Quantum Physics
Baily, Charles; Finkelstein, Noah D.
2010-01-01
The perspectives of introductory classical physics students can often negatively influence how those students later interpret quantum phenomena when taking an introductory course in modern physics. A detailed exploration of student perspectives on the interpretation of quantum physics is needed, both to characterize student understanding of…
Reconciling local realism and quantum physics: a critique to Bell
International Nuclear Information System (INIS)
Claudio Garola.
1994-01-01
A Metatheoretical Generalized Principle (MGP) is stated that formalizes an operational non-standard way of looking at the laws of physics. In Quantum Physics MGP leads to the invalidation of Bell's Inequality without renouncing to a minimal form of realism or to locality. Therefore the violation of Bell's Inequality predicted by Quantum Physics does not appear paradoxial if MGP is accepted
Imagery, Intuition and Imagination in Quantum Physics Education
Stapleton, Andrew J.
2018-01-01
In response to the authors, I demonstrate how threshold concepts offer a means to both contextualise teaching and learning of quantum physics and help transform students into the culture of physics, and as a way to identify particularly troublesome concepts within quantum physics. By drawing parallels from my own doctoral research in another area…
The Qubit as Key to Quantum Physics Part II: Physical Realizations and Applications
Dür, Wolfgang; Heusler, Stefan
2016-01-01
Using the simplest possible quantum system--the qubit--the fundamental concepts of quantum physics can be introduced. This highlights the common features of many different physical systems, and provides a unifying framework when teaching quantum physics at the high school or introductory level. In a previous "TPT" article and in a…
Quantum physics and the beam splitter mystery
Hénault, François
2015-09-01
Optical lossless beam splitters are frequently encountered in fundamental physics experiments regarding the nature of light, including "which-way" determination or the EPR paradox and their measurement apparatus. Although they look as common optical components at first glance, their behaviour remains somewhat mysterious since they apparently exhibit stand-alone particle-like features, and then wave-like characteristics when inserted into a Mach-Zehnder interferometer. In this communication are examined and discussed some basic properties of these beamssplitters, both from a classical optics and quantum physics point of view. Herein the most evident convergences and contradictions are highlighted, and the results of a few emblematic experiments demonstrating photon existence are discussed. Alternative empirical models are also proposed in order to shed light on some remaining issues.
The Quantum Mechanics Solver How to Apply Quantum Theory to Modern Physics
Basdevant, Jean-Louis
2006-01-01
The Quantum Mechanics Solver grew from topics which are part of the final examination in quantum theory at the Ecole Polytechnique at Palaiseau near Paris, France. The aim of the text is to guide the student towards applying quantum mechanics to research problems in fields such as atomic and molecular physics, condensed matter physics, and laser physics. Advanced undergraduates and graduate students will find a rich and challenging source for improving their skills in this field.
Designing quantum information processing via structural physical approximation.
Bae, Joonwoo
2017-10-01
In quantum information processing it may be possible to have efficient computation and secure communication beyond the limitations of classical systems. In a fundamental point of view, however, evolution of quantum systems by the laws of quantum mechanics is more restrictive than classical systems, identified to a specific form of dynamics, that is, unitary transformations and, consequently, positive and completely positive maps to subsystems. This also characterizes classes of disallowed transformations on quantum systems, among which positive but not completely maps are of particular interest as they characterize entangled states, a general resource in quantum information processing. Structural physical approximation offers a systematic way of approximating those non-physical maps, positive but not completely positive maps, with quantum channels. Since it has been proposed as a method of detecting entangled states, it has stimulated fundamental problems on classifications of positive maps and the structure of Hermitian operators and quantum states, as well as on quantum measurement such as quantum design in quantum information theory. It has developed efficient and feasible methods of directly detecting entangled states in practice, for which proof-of-principle experimental demonstrations have also been performed with photonic qubit states. Here, we present a comprehensive review on quantum information processing with structural physical approximations and the related progress. The review mainly focuses on properties of structural physical approximations and their applications toward practical information applications.
Physics student ideas on quantum state and its formal representations
International Nuclear Information System (INIS)
Zuccarini, G.
2014-01-01
Developing a quantum way of thinking is a core and challenging task for physics students. The concept of quantum state, whose physical meaning is connected to the formal structure of the theory, plays an important role in the construction of a quantum perspective and in student difficulties elicited by research. A questionnaire and interview protocol were devised to explore student understanding of the state concept in connection to the properties of its formal representations and to quantum behavior. Results of a calibration of research instruments performed on 6 physics students from different universities are here presented.
Exceptional quantum geometry and particle physics
Directory of Open Access Journals (Sweden)
Michel Dubois-Violette
2016-11-01
Full Text Available Based on an interpretation of the quark–lepton symmetry in terms of the unimodularity of the color group SU(3 and on the existence of 3 generations, we develop an argumentation suggesting that the “finite quantum space” corresponding to the exceptional real Jordan algebra of dimension 27 (the Euclidean Albert algebra is relevant for the description of internal spaces in the theory of particles. In particular, the triality which corresponds to the 3 off-diagonal octonionic elements of the exceptional algebra is associated to the 3 generations of the Standard Model while the representation of the octonions as a complex 4-dimensional space C⊕C3 is associated to the quark–lepton symmetry (one complex for the lepton and 3 for the corresponding quark. More generally it is suggested that the replacement of the algebra of real functions on spacetime by the algebra of functions on spacetime with values in a finite-dimensional Euclidean Jordan algebra which plays the role of “the algebra of real functions” on the corresponding almost classical quantum spacetime is relevant in particle physics. This leads us to study the theory of Jordan modules and to develop the differential calculus over Jordan algebras (i.e. to introduce the appropriate notion of differential forms. We formulate the corresponding definition of connections on Jordan modules.
Time and a physical Hamiltonian for quantum gravity.
Husain, Viqar; Pawłowski, Tomasz
2012-04-06
We present a nonperturbative quantization of general relativity coupled to dust and other matter fields. The dust provides a natural time variable, leading to a physical Hamiltonian with spatial diffeomorphism symmetry. The surprising feature is that the Hamiltonian is not a square root. This property, together with the kinematical structure of loop quantum gravity, provides a complete theory of quantum gravity, and puts applications to cosmology, quantum gravitational collapse, and Hawking radiation within technical reach. © 2012 American Physical Society
Quantum theoretical physics is statistical and relativistic
International Nuclear Information System (INIS)
Harding, C.
1980-01-01
A new theoretical framework for the quantum mechanism is presented. It is based on a strict deterministic behavior of single systems. The conventional QM equation, however, is found to describe statistical results of many classical systems. It will be seen, moreover, that a rigorous synthesis of our theory requires relativistic kinematics. So, QM is not only a classical statistical theory, it is, of necessity, a relativistic theory. The equation of the theory does not just duplicate QM, it indicates an inherent nonlinearity in QM which is subject to experimental verification. It is shown, therefore, that conventional QM is a corollary of classical deterministic principles. It is suggested that this concept of nature conflicts with that prevalent in modern physics. (author)
Inner-shell physics after fifty years of quantum mechanics
International Nuclear Information System (INIS)
Merzbacher, E.
1976-01-01
A historical view is given of how the development of quantum mechanics has been affected by the information relating to inner shells, gathered by physicists since the early days of atomic physics, and of the impact of quantum mechanics on the physics of inner atomic shells. 25 refs
Kizilcik, Hasan Sahin; Yavas, Pervin Ünlü
2017-01-01
The aim of this study is to identify the opinions of pre-service physics teachers about the difficulties in introductory quantum physics topics. In this study conducted with twenty-five pre-service physics teachers, the case study method was used. The participants were interviewed about introductory quantum physics topics. The interviews were…
Exploring quantum physics through hands-on projects
Prutchi, David
2012-01-01
Build an intuitive understanding of the principles behind quantum mechanics through practical construction and replication of original experiments With easy-to-acquire, low-cost materials and basic knowledge of algebra and trigonometry, Exploring Quantum Physics through Hands-on Projects takes readers step by step through the process of re-creating scientific experiments that played an essential role in the creation and development of quantum mechanics. From simple measurements of Planck's constant to testing violations of Bell's inequalities using entangled photons, Exploring Quantum Physics through Hands-on Projects not only immerses readers in the process of quantum mechanics, it provides insight into the history of the field--how the theories and discoveries apply to our world not only today, but also tomorrow. By immersing readers in groundbreaking experiments that can be performed at home, school, or in the lab, this first-ever, hands-on book successfully demystifies the world of quantum physics for...
Scattering and structures essentials and analogies in quantum physics
Povh, Bogdan
2017-01-01
Quantum physics may appear complicated, especially if one forgets the "big picture" and gets lost in the details. However, it can become clearer and less tangled if one applies a few fundamental concepts so that simplified approaches can emerge and estimated orders of magnitude become clear. Povh and Rosina’s Scattering and Structures presents the properties of quantum systems (elementary particles, nucleons, atoms, molecules, quantum gases, quantum liquids, stars, and early universe) with the help of elementary concepts and analogies between these seemingly different systems. In this new edition, sections on quantum gases and an up to date overview of elementary particles have been added.
Green's functions in quantum physics. 3. ed.
International Nuclear Information System (INIS)
Economou, E.N.
2006-01-01
The new edition of a standard reference will be of interest to advanced students wishing to become familiar with the method of Green's functions for obtaining simple and general solutions to basic problems in quantum physics. The main part is devoted to the simplest kind of Green's functions, namely the solutions of linear differential equations with a -function source. It is shown that these familiar Green's functions are a powerful tool for obtaining relatively simple and general solutions of basic problems such as scattering and bound level information. The bound-level treatment gives a clear physical understanding of ''difficult'' questions such as superconductivity, the Kondo effect, and, to a lesser degree, disorder-induced localization. The more advanced subject of many-body Green's functions is presented in the last part of the book. This third edition is 50% longer than the previous and offers end-of-chapter problems and solutions (40% are solved) and additional appendices to help it is to serve as an effective self-tutorial and self-sufficient reference. Throughout, it demonstrates the powerful and unifying formalism of Green's functions across many applications, including transport properties, carbon nanotubes, and photonics and photonic crystals. (orig.)
Meixner, Uwe
2014-01-01
Quantum physics, unlike classical physics, suggests a non-physicalistic metaphysics. Whereas physicalism implies a reductive position in the philosophy of mind, quantum physics is compatible with non-reductionism, and actually seems to support it. The essays in this book explore, from various points of view, the possibilities of basing a non-reductive philosophy of mind on quantum physics.
The Physical Renormalization of Quantum Field Theories
International Nuclear Information System (INIS)
Binger, Michael William.; Stanford U., Phys. Dept.; SLAC
2007-01-01
The profound revolutions in particle physics likely to emerge from current and future experiments motivates an improved understanding of the precise predictions of the Standard Model and new physics models. Higher order predictions in quantum field theories inevitably requires the renormalization procedure, which makes sensible predictions out of the naively divergent results of perturbation theory. Thus, a robust understanding of renormalization is crucial for identifying and interpreting the possible discovery of new physics. The results of this thesis represent a broad set of investigations in to the nature of renormalization. The author begins by motivating a more physical approach to renormalization based on gauge-invariant Green's functions. The resulting effective charges are first applied to gauge coupling unification. This approach provides an elegant formalism for understanding all threshold corrections, and the gauge couplings unify in a more physical manner compared to the usual methods. Next, the gauge-invariant three-gluon vertex is studied in detail, revealing an interesting and rich structure. The effective coupling for the three-gluon vertex, α(k 1 2 , k 2 2 , k 3 2 ), depends on three momentum scales and gives rise to an effective scale Q eff 2 (k 1 2 , k 2 2 , k 3 2 ) which governs the (sometimes surprising) behavior of the vertex. The effects of nonzero internal masses are important and have a complicated threshold and pseudo-threshold structure. The pinch-technique effective charge is also calculated to two-loops and several applications are discussed. The Higgs boson mass in Split Supersymmetry is calculated to two-loops, including all one-loop threshold effects, leading to a downward shift in the Higgs mass of a few GeV. Finally, the author discusses some ideas regarding the overall structure of perturbation theory. This thesis lays the foundation for a comprehensive multi-scale analytic renormalization scheme based on gauge-invariant Green
Quantum physics. 9. tot. rev. and enl. ed.
International Nuclear Information System (INIS)
Gasiorowicz, S.
2005-01-01
This textbook belongs to the mostly favorite and illustrative introductions to quantum physics. The understandable way of presentation allows the independent access of the physical background of the world of quanta. Starting from the physical phenomena the book mediates the fundamental terms and procedures of quantum mechanics and illustrates them by means of extensive application examples and estimations of orders of magnitude. This proximity tro praxis gives to the book its aliveness. For the better understanding Gasiorowicz includes explaining steps and abandons complicated mathematical derivations. The discussion of the physical connections helps in the illustration of formal calculations. By this the successful transition from a course about modern physics to the purely formal development of quantum mechanics is possible. Numerous exercises are found in the extended part of problems. Furthermore the commented list of literature in the appendix is a valuable orientational aid for the study of quantum physics. The 9th edition was completely surveyed, actualized, and extended
Are quantum-mechanical-like models possible, or necessary, outside quantum physics?
International Nuclear Information System (INIS)
Plotnitsky, Arkady
2014-01-01
This article examines some experimental conditions that invite and possibly require recourse to quantum-mechanical-like mathematical models (QMLMs), models based on the key mathematical features of quantum mechanics, in scientific fields outside physics, such as biology, cognitive psychology, or economics. In particular, I consider whether the following two correlative features of quantum phenomena that were decisive for establishing the mathematical formalism of quantum mechanics play similarly important roles in QMLMs elsewhere. The first is the individuality and discreteness of quantum phenomena, and the second is the irreducibly probabilistic nature of our predictions concerning them, coupled to the particular character of the probabilities involved, as different from the character of probabilities found in classical physics. I also argue that these features could be interpreted in terms of a particular form of epistemology that suspends and even precludes a causal and, in the first place, realist description of quantum objects and processes. This epistemology limits the descriptive capacity of quantum theory to the description, classical in nature, of the observed quantum phenomena manifested in measuring instruments. Quantum mechanics itself only provides descriptions, probabilistic in nature, concerning numerical data pertaining to such phenomena, without offering a physical description of quantum objects and processes. While QMLMs share their use of the quantum-mechanical or analogous mathematical formalism, they may differ by the roles, if any, the two features in question play in them and by different ways of interpreting the phenomena they considered and this formalism itself. This article will address those differences as well. (paper)
Quantum simulations with photons and polaritons merging quantum optics with condensed matter physics
2017-01-01
This book reviews progress towards quantum simulators based on photonic and hybrid light-matter systems, covering theoretical proposals and recent experimental work. Quantum simulators are specially designed quantum computers. Their main aim is to simulate and understand complex and inaccessible quantum many-body phenomena found or predicted in condensed matter physics, materials science and exotic quantum field theories. Applications will include the engineering of smart materials, robust optical or electronic circuits, deciphering quantum chemistry and even the design of drugs. Technological developments in the fields of interfacing light and matter, especially in many-body quantum optics, have motivated recent proposals for quantum simulators based on strongly correlated photons and polaritons generated in hybrid light-matter systems. The latter have complementary strengths to cold atom and ion based simulators and they can probe for example out of equilibrium phenomena in a natural driven-dissipative sett...
Quantum-like behavior without quantum physics I : Kinematics of neural-like systems.
Selesnick, S A; Rawling, J P; Piccinini, Gualtiero
2017-09-01
Recently there has been much interest in the possible quantum-like behavior of the human brain in such functions as cognition, the mental lexicon, memory, etc., producing a vast literature. These studies are both empirical and theoretical, the tenets of the theory in question being mainly, and apparently inevitably, those of quantum physics itself, for lack of other arenas in which quantum-like properties are presumed to obtain. However, attempts to explain this behavior on the basis of actual quantum physics going on at the atomic or molecular level within some element of brain or neuronal anatomy (other than the ordinary quantum physics that underlies everything), do not seem to survive much scrutiny. Moreover, it has been found empirically that the usual physics-like Hilbert space model seems not to apply in detail to human cognition in the large. In this paper we lay the groundwork for a theory that might explain the provenance of quantum-like behavior in complex systems whose internal structure is essentially hidden or inaccessible. The approach is via the logic obeyed by these systems which is similar to, but not identical with, the logic obeyed by actual quantum systems. The results reveal certain effects in such systems which, though quantum-like, are not identical to the kinds of quantum effects found in physics. These effects increase with the size of the system.
QBism the future of quantum physics
von Baeyer, Hans Christian
2016-01-01
Measured by the accuracy of its predictions and the scope of its technological applications, quantum mechanics is one of the most successful theories in science--as well as one of the most misunderstood. The deeper meaning of quantum mechanics remains controversial almost a century after its invention. Providing a way past quantum theory's paradoxes and puzzles, QBism offers a strikingly new interpretation that opens up for the nonspecialist reader the profound implications of quantum mechanics for how we understand and interact with the world. Short for Quantum Bayesianism, QBism adapts many of the conventional features of quantum mechanics in light of a revised understanding of probability. Bayesian probability, unlike the standard "frequentist probability," is defined as a numerical measure of the degree of an observer's belief that a future event will occur or that a particular proposition is true. Bayesianism's advantages over frequentist probability are that it is applicable to singular events, its pro...
Quantum physics on the edge of chaos
Energy Technology Data Exchange (ETDEWEB)
Berry, M
1987-11-19
The phenomena of quantum chaology lies in the largely unexplored border country between quantum and classical mechanics - they are part of semiclassical mechanics. Quantum chaology is an emerging science that is leading to the discovery of unfamiliar regimes of behavior in microscopic systems, and concerns whether quantum systems become chaotic as they approach the classical limit. The case of how electrons in highly excited states absorb energy from radiation shining on them is discussed. Quantum chaology of systems that are either isolated, or else are influenced by external forces that do not vary are also examined. Finally, the connection between the Rieman hypothesis of number theory and quantum chaology is described. (U.K.).
The quantum mechanics solver. How to apply quantum theory to modern physics. 2. ed.
International Nuclear Information System (INIS)
Basdevant, J.L.; Dalibard, J.
2006-01-01
The Quantum Mechanics Solver uniquely illustrates the application of quantum mechanical concepts to various fields of modern physics. It aims at encouraging the reader to apply quantum mechanics to research problems in fields such as molecular physics, condensed matter physics or laser physics. Advanced undergraduates and graduate students will find a rich and challenging source of material for further exploration. This book consists of a series of problems concerning present-day experimental or theoretical questions on quantum mechanics. All of these problems are based on actual physical examples, even if sometimes the mathematical structure of the models under consideration is simplified intentionally in order to get hold of the physics more rapidly. The new edition features new themes, such as the progress in measuring neutrino oscillations, quantum boxes, the quantum thermometer etc. Secondly, it includes a brief summary on the basics of quantum mechanics and the formalism we use. Finally, the problems under three main themes: Elementary Particles, Nuclei and Atoms; Quantum Entanglement and Measurement; and Complex Systems. (orig.)
Maxwell's equations, quantum physics and the quantum graviton
International Nuclear Information System (INIS)
Gersten, Alexander; Moalem, Amnon
2011-01-01
Quantum wave equations for massless particles and arbitrary spin are derived by factorizing the d'Alembertian operator. The procedure is extensively applied to the spin one photon equation which is related to Maxwell's equations via the proportionality of the photon wavefunction Ψ to the sum E + iB of the electric and magnetic fields. Thus Maxwell's equations can be considered as the first quantized one-photon equation. The photon wave equation is written in two forms, one with additional explicit subsidiary conditions and second with the subsidiary conditions implicitly included in the main equation. The second equation was obtained by factorizing the d'Alembertian with 4×4 matrix representation of 'relativistic quaternions'. Furthermore, scalar Lagrangian formalism, consistent with quantization requirements is developed using derived conserved current of probability and normalization condition for the wavefunction. Lessons learned from the derivation of the photon equation are used in the derivation of the spin two quantum equation, which we call the quantum graviton. Quantum wave equation with implicit subsidiary conditions, which factorizes the d'Alembertian with 8×8 matrix representation of relativistic quaternions, is derived. Scalar Lagrangian is formulated and conserved probability current and wavefunction normalization are found, both consistent with the definitions of quantum operators and their expectation values. We are showing that the derived equations are the first quantized equations of the photon and the graviton.
International Conference on Laser Physics and Quantum Optics
Xie, Shengwu; Zhu, Shi-Yao; Scully, Marlan
2000-01-01
Since the advent of the laser about 40 years ago, the field of laser physics and quantum optics have evolved into a major discipline. The early studies included the optical coherence theory and the semiclassical and quantum mechanical theories of the laser. More recently many new and interesting effects have been predicted. These include the role of coherent atomic effects in lasing without inversion and electromagnetically induced transparency, atom optics, laser cooling and trapping, teleportation, the single-atom micromaser and its role in quantum measurement theory, to name a few. The International Conference on Laser Physics and Quantum Optics was held in Shanghai from August 25 to August 28, 1999, to discuss these and many other exciting developments in laser physics and quantum optics. The international character of the conference was manifested by the fact that scientists from over 13 countries participated and lectured at the conference. There were four keynote lectures delivered by Nobel laureate Wi...
Topological quantum numbers in nonrelativistic physics
Thouless, David James
1998-01-01
Topological quantum numbers are distinguished from quantum numbers based on symmetry because they are insensitive to the imperfections of the systems in which they are observed. They have become very important in precision measurements in recent years, and provide the best measurements of voltage and electrical resistance. This book describes the theory of such quantum numbers, starting with Dirac's argument for the quantization of electric charge, and continuing with discussions on the helium superfluids, flux quantization and the Josephson effect in superconductors, the quantum Hall effect,
QIPS: quantum information and quantum physics in space
Schmitt-Manderbach, Tobias; Scheidl, Thomas; Ursin, Rupert; Tiefenbacher, Felix; Weier, Henning; Fürst, Martin; Jennewein, T.; Perdigues, J.; Sodnik, Z.; Rarity, J.; Zeilinger, Anton; Weinfurter, Harald
2017-11-01
The aim of the QIPS project (financed by ESA) is to explore quantum phenomena and to demonstrate quantum communication over long distances. Based on the current state-of-the-art a first study investigating the feasibility of space based quantum communication has to establish goals for mid-term and long-term missions, but also has to test the feasibility of key issues in a long distance ground-to-ground experiment. We have therefore designed a proof-of-concept demonstration for establishing single photon links over a distance of 144 km between the Canary Islands of La Palma and Tenerife to evaluate main limitations for future space experiments. Here we report on the progress of this project and present first measurements of crucial parameters of the optical free space link.
Teaching and Understanding of Quantum Interpretations in Modern Physics Courses
Baily, Charles; Finkelstein, Noah D.
2010-01-01
Just as expert physicists vary in their personal stances on interpretation in quantum mechanics, instructors vary on whether and how to teach interpretations of quantum phenomena in introductory modern physics courses. In this paper, we document variations in instructional approaches with respect to interpretation in two similar modern physics…
How to teach quantum physics to your dog
Orzel, Chad
2010-01-01
In this international bestseller, Orzel explains the key theories of quantum physics, taking his dog Emmy's anarchic behaviour as a starting point. Could she use quantum tunnelling to get through the neighbour's fence? How about diffracting round a tree to chase squirrels? From quarks and gluons to Heisenberg's uncertainty principle, this is a uniquely entertaining way to unlock the secrets of the universe.
Consistent Quantum Histories: Towards a Universal Language of Physics
International Nuclear Information System (INIS)
Grygiel, W.P.
2007-01-01
The consistent histories interpretation of quantum mechanics is a reformulation of the standard Copenhagen interpretation that aims at incorporating quantum probabilities as part of the axiomatic foundations of the theory. It is not only supposed to equip quantum mechanics with clear criteria of its own experimental verification but, first and foremost, to alleviate one of the stumbling blocks of the theory - the measurement problem. Since the consistent histories interpretation operates with a series of quantum events integrated into one quantum history, the measurement problem is naturally absorbed as one of the events that build up a history. The interpretation rests upon the two following assumptions, proposed already by J. von Neumann: (1) both the microscopic and macroscopic regimes are subject to the same set of quantum laws and (2) a projector operator that is assigned to each event within a history permits to transcribe the history into a set of propositions that relate the entire course of quantum events. Based on this, a universal language of physics is expected to emerge that will bring the quantum apparatus back to common sense propositional logic. The basic philosophical issue raised this study is whether one should justify quantum mechanics by means of what emerges from it, that is, the properties of the macroscopic world, or use the axioms of quantum mechanics to demonstrate the mechanisms how the macroscopic world comes about from the quantum regime. (author)
Quantum physics in the nanoworld. Schroedinger's cat and the dwarfs
International Nuclear Information System (INIS)
Lueth, Hans
2013-01-01
Gives a step-by-step derivation of the physical basis of quantum mechanics without using complex mathematics. Provides a close linking of experiment and theory. Describes most modern experiments related to nanoscience and to the foundation of quantum theory. Provides appendices describing the preparation of nanostructures and the importance of interface physics for nanoscience. Contains more than 40 problems to deepen the understanding. English language version of a successful German textbook. The book deals with all essential aspects of non-relativistic quantum physics up to the quantization of fields. In contrast to common textbooks of quantum mechanics, modern experiments are described both for the purpose of foundation of the theory and in relation to recent applications. In this respect applications to nano-electronics as well as the realization of quantum-bits are presented and discussed. Furthermore, links are made to other important research fields and applications, such as elementary particle physics, solid state physics and nuclear magnetic resonance tomography in medicine. Even though the representation of the topics is largely performed in terms of Dirac's bra-ket notation and by use of commutator algebra, the concrete description of the physical basis and the corresponding theoretical concepts are emphasized. Because of little requirement of complex mathematics, the book is suitable as an introduction into quantum physics, not only for physicists but also for chemists, biologists, engineers, computer scientists and even for philosophers as far as they are interested in natural philosophy and epistomology.
Quantum potential physics, geometry and algebra
Licata, Ignazio
2014-01-01
Recently the interest in Bohm realist interpretation of quantum mechanics has grown. The important advantage of this approach lies in the possibility to introduce non-locality ab initio, and not as an “unexpected host”. In this book the authors give a detailed analysis of quantum potential, the non-locality term and its role in quantum cosmology and information. The different approaches to the quantum potential are analysed, starting from the original attempt to introduce a realism of particles trajectories (influenced by de Broglie’s pilot wave) to the recent dynamic interpretation provided by Goldstein, Durr, Tumulka and Zanghì, and the geometrodynamic picture, with suggestion about quantum gravity. Finally we focus on the algebraic reading of Hiley and Birkbeck school, that analyse the meaning of the non-local structure of the world, bringing important consequences for the space, time and information concepts.
Reflections on the information paradigm in quantum and gravitational physics
Andres Höhn, Philipp
2017-08-01
We reflect on the information paradigm in quantum and gravitational physics and on how it may assist us in approaching quantum gravity. We begin by arguing, using a reconstruction of its formalism, that quantum theory can be regarded as a universal framework governing an observer’s acquisition of information from physical systems taken as information carriers. We continue by observing that the structure of spacetime is encoded in the communication relations among observers and more generally the information flow in spacetime. Combining these insights with an information-theoretic Machian view, we argue that the quantum architecture of spacetime can operationally be viewed as a locally finite network of degrees of freedom exchanging information. An advantage - and simultaneous limitation - of an informational perspective is its quasi-universality, i.e. quasi-independence of the precise physical incarnation of the underlying degrees of freedom. This suggests to exploit these informational insights to develop a largely microphysics independent top-down approach to quantum gravity to complement extant bottom-up approaches by closing the scale gap between the unknown Planck scale physics and the familiar physics of quantum (field) theory and general relativity systematically from two sides. While some ideas have been pronounced before in similar guise and others are speculative, the way they are strung together and justified is new and supports approaches attempting to derive emergent spacetime structures from correlations of quantum degrees of freedom.
Quantum Physics A First Encounter Interference, Entanglement, and Reality
Scarani, Valerio
2006-01-01
The essential features of quantum physics, largely debated since its discovery, are presented in this book, through the description (without mathematics) of recent experiments. Putting the accent on physical phenomena, this book clarifies the historical issues (delocalisation, interferences) and reaches out to modern topics (quantum cryptography, non-locality and teleportation); the debate on interpretations is serenely reviewed. - ;Quantum physics is often perceived as a weird and abstract theory, which physicists must use in order to make correct predictions. But many recent experiments have shown that the weirdness of the theory simply mirrors the weirdness of phenomena: it is Nature itself, and not only our description of it, that behaves in an astonishing way. This book selects those, among these typical quantum phenomena, whose rigorous description requires neither the formalism, nor an important. background in physics. The first part of the book deals with the phenomenon of single-particle interference...
Quantum Chromodynamics and nuclear physics at extreme energy density
International Nuclear Information System (INIS)
Mueller, B.
1993-01-01
This report discusses research in the following topics: Hadron structure physics; relativistic heavy ion collisions; finite- temperature QCD; real-time lattice gauge theory; and studies in quantum field theory
A Novel Hypothesis for Quantum Physics, Model with Telegraphs Equation
Czech Academy of Sciences Publication Activity Database
Fiala, P.; Bartušek, Karel; Steinbauer, M.
2008-01-01
Roč. 4, č. 4 (2008), s. 425-428 ISSN 1931-7360 Institutional research plan: CEZ:AV0Z20650511 Keywords : quantum physics * material wave the ory * MWT Subject RIV: JA - Electron ics ; Optoelectronics, Electrical Engineering
Atomtronics: Material and Device Physics of Quantum Gases
matter physics to electrical engineering. Our projects title Atomtronics: Material and device physics of quantum gases illustrates the chasm we bridged...starting from therich and fundamental physics already revealed with cold atoms systems, then leading to an understanding of the functional materials
Quantum theory. Foundations of modern physics. 5. upd. ed.
International Nuclear Information System (INIS)
Ingold, Gert-Ludwig
2015-01-01
In the december of the year 1900n the famous physicist Max Planck gave a lecture, which should be later called as the birth hour of quantum physics. Their statements and knowledges should revolutionize our picture of the world in a hardly thought possible radicality and form meanwhile a central base for our understanding of nature. This book mediates an experienced, compact survey about the most important elements of modern quantum physics and their amazing, our common experience seemingly contradicting consequences.
Computational physics simulation of classical and quantum systems
Scherer, Philipp O J
2017-01-01
This textbook presents basic numerical methods and applies them to a large variety of physical models in multiple computer experiments. Classical algorithms and more recent methods are explained. Partial differential equations are treated generally comparing important methods, and equations of motion are solved by a large number of simple as well as more sophisticated methods. Several modern algorithms for quantum wavepacket motion are compared. The first part of the book discusses the basic numerical methods, while the second part simulates classical and quantum systems. Simple but non-trivial examples from a broad range of physical topics offer readers insights into the numerical treatment but also the simulated problems. Rotational motion is studied in detail, as are simple quantum systems. A two-level system in an external field demonstrates elementary principles from quantum optics and simulation of a quantum bit. Principles of molecular dynamics are shown. Modern bounda ry element methods are presented ...
Structure and unity. Trancendence-philosophical interpretation of quantum physics
International Nuclear Information System (INIS)
Lambrecht, Juergen
2013-01-01
Since their beginnings at the begin of the 20th century quantum physics in the ontological and epistemological interpretation of their results is facing persistent difficulties, which could not be satisfactorily solved to this day. Some quantum phenomena are beyond of both our everyday understanding of the world and the classical-physical picture of the world, which is essentially based on the mechanics of Isaac Newton. They exceed our imagination and seem at least partly contradict logical and space-time laws. Transcendence-philosophical thinking, which exhibits a close structural relation to the logics of Georg Wilhelm Friedrich Hegel and to the philosophical systems analysis, provides a set of methodological instruments, which can help to avoid some problems of quantum-theoretical interpretation, which are in striking contrast to the mathematically consistent formulation of quantum theory. This is paradigmatically shown by selected main themes of the quantum-theoretical discussion.
Einsteins' apparition. Teleportation and further mysteries of quantum physics
International Nuclear Information System (INIS)
Zeilinger, A.
2005-01-01
The author, renomated professor of experimental physics at Vienna, had proven it: teleportation is possible. But how does it work, and what chances are in it? ''Einsteins' apparition'' presents also for non-scientists an understandable, vividly written and yet comprehensive introduction to quantum physics - a scientific field, hardly sizeable by common sense, but that's just why fascinating enormously. But also practically minded persons get one's money's worth by the author: futural applications like about quantum computers or data transmission by quantum communication will change our everyday life fundamentally - even if the ''beaming'' of man belongs further in the science fiction field. (GL)
Atomic physics and quantum optics using superconducting circuits.
You, J Q; Nori, Franco
2011-06-29
Superconducting circuits based on Josephson junctions exhibit macroscopic quantum coherence and can behave like artificial atoms. Recent technological advances have made it possible to implement atomic-physics and quantum-optics experiments on a chip using these artificial atoms. This Review presents a brief overview of the progress achieved so far in this rapidly advancing field. We not only discuss phenomena analogous to those in atomic physics and quantum optics with natural atoms, but also highlight those not occurring in natural atoms. In addition, we summarize several prospective directions in this emerging interdisciplinary field.
International Nuclear Information System (INIS)
Ohba, Ichiro; Aizawa, Yoji; Daishido, Tsuneaki; Kurihara, Susumu; Maeda, Kei-ichi; Nakazato, Hiromichi; Tasaki, Shuichi; Yuasa, Kazuya
2003-11-01
Waseda International Symposium on Fundamental Physics - New Perspectives in Quantum Physics - was held on November 12-15, 2002 at International Conference Hall (IBUKA HALL), Waseda University, Tokyo, Japan. This symposium was organized to provide an opportunity to verify fundamental physics attainments and to discuss new prospectives in quantum physics in the 21st century. These themes of the symposium were reexamined from all aspects in terms of important key words of the symposium, fundamental quantum theory, quantum coherence and decoherence, quantum chaos, time symmetry breaking, Bose-Einstein condensation and quantum information and computation. Separate abstracts were presented for 12 of the papers in this report. The remaining 40 were considered outside the subject scope of INIS. (J.P.N.)
Compendium of quantum physics. Concepts, experiments, history and philosophy
International Nuclear Information System (INIS)
Greenberger, Daniel; Hentschel, Klaus; Weinert, Friedel
2009-01-01
With contributions by many of today's leading quantum physicists, philosophers and historians, including three Nobel laureates, this comprehensive A to Z of quantum physics provides a lucid understanding of the key concepts of quantum theory and experiment. It covers technical and interpretational aspects alike, and includes both traditional topics and newer areas such as quantum information and its relatives. The central concepts that have shaped contemporary understanding of the quantum world are clearly defined, with illustrations where helpful, and discussed at a level suitable for undergraduate and graduate students of physics, history of science, and philosophy of physics. All articles share three main aims: (1) to provide a clear definition and understanding of the term concerned; (2) where possible, to trace the historical origins of the concept; and (3) to provide a small but optimal selection of references to the most relevant literature, including pertinent historical studies. Also discussed are the often contentious philosophical implications derived from quantum theory and its associated experimental findings. This compendium will be an indispensable resource for all those seeking concise up-to-date information about the many facets of quantum physics. (orig.)
Computer science: Data analysis meets quantum physics
Schramm, Steven
2017-10-01
A technique that combines machine learning and quantum computing has been used to identify the particles known as Higgs bosons. The method could find applications in many areas of science. See Letter p.375
International Conference on Quantum Mathematical Physics : a Bridge between Mathematics and Physics
Kleiner, Johannes; Röken, Christian; Tolksdorf, Jürgen
2016-01-01
Quantum physics has been highly successful for more than 90 years. Nevertheless, a rigorous construction of interacting quantum field theory is still missing. Moreover, it is still unclear how to combine quantum physics and general relativity in a unified physical theory. Attacking these challenging problems of contemporary physics requires highly advanced mathematical methods as well as radically new physical concepts. This book presents different physical ideas and mathematical approaches in this direction. It contains a carefully selected cross-section of lectures which took place in autumn 2014 at the sixth conference ``Quantum Mathematical Physics - A Bridge between Mathematics and Physics'' in Regensburg, Germany. In the tradition of the other proceedings covering this series of conferences, a special feature of this book is the exposition of a wide variety of approaches, with the intention to facilitate a comparison. The book is mainly addressed to mathematicians and physicists who are interested in fu...
Refined characterization of student perspectives on quantum physics
Directory of Open Access Journals (Sweden)
Charles Baily
2010-09-01
Full Text Available The perspectives of introductory classical physics students can often negatively influence how those students later interpret quantum phenomena when taking an introductory course in modern physics. A detailed exploration of student perspectives on the interpretation of quantum physics is needed, both to characterize student understanding of physics concepts, and to inform how we might teach traditional content. Our previous investigations of student perspectives on quantum physics have indicated they can be highly nuanced, and may vary both within and across contexts. In order to better understand the contextual and often seemingly contradictory stances of students on matters of interpretation, we interviewed 19 students from four introductory modern physics courses taught at the University of Colorado. We find that students have attitudes and opinions that often parallel the stances of expert physicists when arguing for their favored interpretations of quantum mechanics, allowing for more nuanced characterizations of student perspectives in terms of three key interpretive themes. We present a framework for characterizing student perspectives on quantum mechanics, and demonstrate its utility in interpreting the sometimes contradictory nature of student responses to previous surveys. We further find that students most often vacillate in their responses when what makes intuitive sense to them is not in agreement with what they consider to be a correct response, underscoring the need to distinguish between the personal and the public perspectives of introductory modern physics students.
Inverse problems in classical and quantum physics
International Nuclear Information System (INIS)
Almasy, A.A.
2007-01-01
The subject of this thesis is in the area of Applied Mathematics known as Inverse Problems. Inverse problems are those where a set of measured data is analysed in order to get as much information as possible on a model which is assumed to represent a system in the real world. We study two inverse problems in the fields of classical and quantum physics: QCD condensates from tau-decay data and the inverse conductivity problem. Despite a concentrated effort by physicists extending over many years, an understanding of QCD from first principles continues to be elusive. Fortunately, data continues to appear which provide a rather direct probe of the inner workings of the strong interactions. We use a functional method which allows us to extract within rather general assumptions phenomenological parameters of QCD (the condensates) from a comparison of the time-like experimental data with asymptotic space-like results from theory. The price to be paid for the generality of assumptions is relatively large errors in the values of the extracted parameters. Although we do not claim that our method is superior to other approaches, we hope that our results lend additional confidence to the numerical results obtained with the help of methods based on QCD sum rules. EIT is a technology developed to image the electrical conductivity distribution of a conductive medium. The technique works by performing simultaneous measurements of direct or alternating electric currents and voltages on the boundary of an object. These are the data used by an image reconstruction algorithm to determine the electrical conductivity distribution within the object. In this thesis, two approaches of EIT image reconstruction are proposed. The first is based on reformulating the inverse problem in terms of integral equations. This method uses only a single set of measurements for the reconstruction. The second approach is an algorithm based on linearisation which uses more then one set of measurements. A
Inverse problems in classical and quantum physics
Energy Technology Data Exchange (ETDEWEB)
Almasy, A.A.
2007-06-29
The subject of this thesis is in the area of Applied Mathematics known as Inverse Problems. Inverse problems are those where a set of measured data is analysed in order to get as much information as possible on a model which is assumed to represent a system in the real world. We study two inverse problems in the fields of classical and quantum physics: QCD condensates from tau-decay data and the inverse conductivity problem. Despite a concentrated effort by physicists extending over many years, an understanding of QCD from first principles continues to be elusive. Fortunately, data continues to appear which provide a rather direct probe of the inner workings of the strong interactions. We use a functional method which allows us to extract within rather general assumptions phenomenological parameters of QCD (the condensates) from a comparison of the time-like experimental data with asymptotic space-like results from theory. The price to be paid for the generality of assumptions is relatively large errors in the values of the extracted parameters. Although we do not claim that our method is superior to other approaches, we hope that our results lend additional confidence to the numerical results obtained with the help of methods based on QCD sum rules. EIT is a technology developed to image the electrical conductivity distribution of a conductive medium. The technique works by performing simultaneous measurements of direct or alternating electric currents and voltages on the boundary of an object. These are the data used by an image reconstruction algorithm to determine the electrical conductivity distribution within the object. In this thesis, two approaches of EIT image reconstruction are proposed. The first is based on reformulating the inverse problem in terms of integral equations. This method uses only a single set of measurements for the reconstruction. The second approach is an algorithm based on linearisation which uses more then one set of measurements. A
50 quantum physics ideas you really need to know
Baker, Joanne
2013-01-01
Following on from the highly successful 50 Physics Ideas You Really Need to Know, author Joanne Baker consolidates the foundation concepts of physics and moves on to present clear explanations of the most cutting-edge area of science: quantum physics. With 50 concise chapters covering complex theories and their advanced applications - from string theory to black holes, and quarks to quantum computing - alongside informative two-colour illustrations, this book presents key ideas in straightforward, bite-sized chunks. Ideal for the layperson, this book will challenge the way you understand the world. The ideas explored include: Theory of relativity; Schrodinger's cat; Nuclear forces: fission and fusion; Antimatter; Superconductivity.
Approximating the physical inner product of loop quantum cosmology
International Nuclear Information System (INIS)
Bahr, Benjamin; Thiemann, Thomas
2007-01-01
In this paper, we investigate the possibility of approximating the physical inner product of constrained quantum theories. In particular, we calculate the physical inner product of a simple cosmological model in two ways: firstly, we compute it analytically via a trick; secondly, we use the complexifier coherent states to approximate the physical inner product defined by the master constraint of the system. We find that the approximation is able to recover the analytic solution of the problem, which consolidates hopes that coherent states will help to approximate solutions of more complicated theories, like loop quantum gravity
Designing learning environments to teach interactive Quantum Physics
Gómez Puente, Sonia M.; Swagten, Henk J. M.
2012-10-01
This study aims at describing and analysing systematically an interactive learning environment designed to teach Quantum Physics, a second-year physics course. The instructional design of Quantum Physics is a combination of interactive lectures (using audience response systems), tutorials and self-study in unit blocks, carried out with small groups. Individual formative feedback was introduced as a rapid assessment tool to provide an overview on progress and identify gaps by means of questioning students at three levels: conceptual; prior knowledge; homework exercises. The setup of Quantum Physics has been developed as a result of several loops of adjustments and improvements from a traditional-like type of teaching to an interactive classroom. Results of this particular instructional arrangement indicate significant gains in students' achievements in comparison with the traditional structure of this course, after recent optimisation steps such as the implementation of an individual feedback system.
Making the Transition from Classical to Quantum Physics
Dutt, Amit
2011-01-01
This paper reports on the nature of the conceptual understandings developed by Year 12 Victorian Certificate of Education (VCE) physics students as they made the transition from the essentially deterministic notions of classical physics, to interpretations characteristic of quantum theory. The research findings revealed the fact that the…
Pre-Service Physics Teachers' Comprehension of Quantum Mechanical Concepts
Didis, Nilufer; Eryilmaz, Ali; Erkoc, Sakir
2010-01-01
When quantum theory caused a paradigm shift in physics, it introduced difficulties in both learning and teaching of physics. Because of its abstract, counter-intuitive and mathematical structure, students have difficulty in learning this theory, and instructors have difficulty in teaching the concepts of the theory. This case study investigates…
Ad Hoc Physical Hilbert Spaces in Quantum Mechanics
Czech Academy of Sciences Publication Activity Database
Fernandez, F. M.; Garcia, J.; Semorádová, Iveta; Znojil, Miloslav
2015-01-01
Roč. 54, č. 12 (2015), s. 4187-4203 ISSN 0020-7748 Institutional support: RVO:61389005 Keywords : quantum mechanics * physical Hilbert spaces * ad hoc inner product * singular potentials regularized * low lying energies Subject RIV: BE - Theoretical Physics Impact factor: 1.041, year: 2015
Quantum physics as challenge of the theory of perception
International Nuclear Information System (INIS)
Czasny, Karl
2010-01-01
The author indicates a totally new way to the philosophical work with the modern physics, especially the quantum mechanics. Like Galilei has the experiment, so an action, integrated in the physical process of perception, the author takes the acting also up in the philosophical analysis. The result is fascinating and original.
Quantum physics. Vol. 2. From time-dependent dynamics to many-body physics and quantum chaos
International Nuclear Information System (INIS)
Zelevinsky, Vladimir
2011-01-01
This two-volume set can be naturally divided into two semester courses, and contains a full modern graduate course in quantum physics. The idea is to teach graduate students how to practically use quantum physics and theory, presenting the fundamental knowledge, and gradually moving on to applications, including atomic, nuclear and solid state physics, as well as modern subfields, such as quantum chaos and quantum entanglement. The book starts with basic quantum problems, which do not require full quantum formalism but allow the student to gain the necessary experience and elements of quantum thinking. Only then does the fundamental Schrodinger equation appear. The author has included topics that are not usually covered in standard textbooks and has written the book in such a way that every topic contains varying layers of difficulty, so that the instructor can decide where to stop. Although supplementary sources are not required, ''Further reading'' is given for each chapter, including references to scientific journals and publications, and a glossary is also provided. Problems and solutions are integrated throughout the text. (orig.)
Quantum physics. Vol. 2. From time-dependent dynamics to many-body physics and quantum chaos
Energy Technology Data Exchange (ETDEWEB)
Zelevinsky, Vladimir [NSCL Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy
2011-07-01
This two-volume set can be naturally divided into two semester courses, and contains a full modern graduate course in quantum physics. The idea is to teach graduate students how to practically use quantum physics and theory, presenting the fundamental knowledge, and gradually moving on to applications, including atomic, nuclear and solid state physics, as well as modern subfields, such as quantum chaos and quantum entanglement. The book starts with basic quantum problems, which do not require full quantum formalism but allow the student to gain the necessary experience and elements of quantum thinking. Only then does the fundamental Schrodinger equation appear. The author has included topics that are not usually covered in standard textbooks and has written the book in such a way that every topic contains varying layers of difficulty, so that the instructor can decide where to stop. Although supplementary sources are not required, ''Further reading'' is given for each chapter, including references to scientific journals and publications, and a glossary is also provided. Problems and solutions are integrated throughout the text. (orig.)
Knot theory and a physical state of quantum gravity
International Nuclear Information System (INIS)
Liko, Tomas; Kauffman, Louis H
2006-01-01
We discuss the theory of knots, and describe how knot invariants arise naturally in gravitational physics. The focus of this review is to delineate the relationship between knot theory and the loop representation of non-perturbative canonical quantum general relativity (loop quantum gravity). This leads naturally to a discussion of the Kodama wavefunction, a state which is conjectured to be the ground state of the gravitational field with positive cosmological constant. This review can serve as a self-contained introduction to loop quantum gravity and related areas. Our intent is to make the paper accessible to a wider audience that may include topologists, knot theorists, and other persons innocent of the physical background to this approach to quantum gravity. (topical review)
The Oxford Questions on the foundations of quantum physics.
Briggs, G A D; Butterfield, J N; Zeilinger, A
2013-09-08
The twentieth century saw two fundamental revolutions in physics-relativity and quantum. Daily use of these theories can numb the sense of wonder at their immense empirical success. Does their instrumental effectiveness stand on the rock of secure concepts or the sand of unresolved fundamentals? Does measuring a quantum system probe, or even create, reality or merely change belief? Must relativity and quantum theory just coexist or might we find a new theory which unifies the two? To bring such questions into sharper focus, we convened a conference on Quantum Physics and the Nature of Reality. Some issues remain as controversial as ever, but some are being nudged by theory's secret weapon of experiment.
Generation of quantum logic operations from physical Hamiltonians
International Nuclear Information System (INIS)
Zhang Jun; Whaley, K. Birgitta
2005-01-01
We provide a systematic analysis of the physical generation of single- and two-qubit quantum operations from Hamiltonians available in various quantum systems for scalable quantum information processing. We show that generation of single-qubit operations can be transformed into a steering problem on the Bloch sphere, which represents all R z -equivalence classes of single-qubit operations, whereas the two-qubit problem can be generally transformed into a steering problem in a tetrahedron representing all the local-equivalence classes of two-qubit operations (the Weyl chamber). We use this approach to investigate several physical examples for the generation of two-qubit operations. The steering approach provides useful guidance for the realization of various quantum computation schemes
Physical-resource requirements and the power of quantum computation
International Nuclear Information System (INIS)
Caves, Carlton M; Deutsch, Ivan H; Blume-Kohout, Robin
2004-01-01
The primary resource for quantum computation is the Hilbert-space dimension. Whereas Hilbert space itself is an abstract construction, the number of dimensions available to a system is a physical quantity that requires physical resources. Avoiding a demand for an exponential amount of these resources places a fundamental constraint on the systems that are suitable for scalable quantum computation. To be scalable, the number of degrees of freedom in the computer must grow nearly linearly with the number of qubits in an equivalent qubit-based quantum computer. These considerations rule out quantum computers based on a single particle, a single atom, or a single molecule consisting of a fixed number of atoms or on classical waves manipulated using the transformations of linear optics
Quantum technologies for solid state physics using cold trapped ions
International Nuclear Information System (INIS)
Ferdinand Schmidt-Kaler
2014-01-01
The quantum states of ions are perfectly controlled, and may be used for fundamental research in quantum physics, as highlighted by the Nobel Prize given to Dave Wineland in 2012. Two directions of quantum technologies, followed by the Mainz group, have high impact on solid state physics: I) The delivery of single cold ions on demand for the deterministic doping of solid state materials with nm spatial precision to generate design-structures optimized for quantum processors. II) The simulation of solid state relevant Hamiltonians with AMO systems of one or two dimensional arrays of trapped ions. I will talk about the recent progress in both fields. http://www.quantenbit.de/#Number Sign#/publications/(author)
Atomic physics tests of quantum electrodynamics
International Nuclear Information System (INIS)
Mohr, P.J.
1976-08-01
The tests of quantum electrodynamics derived from bound systems and the free electron and muon magnetic moments are reviewed. The emphasis is on the areas in which recent developments in theory or experiment have taken place. Also determinations of the fine structure constant from the Josephson effect and the fine structure of helium are discussed
Quantum physics and linguistics a compositional, diagrammatic discourse
Grefenstette, Edward; Heunen, Chris
2013-01-01
New scientific paradigms typically consist of an expansion of the conceptual language with which we describe the world. Over the past decade, theoretical physics and quantum information theory have turned to category theory to model and reason about quantum protocols. This new use of categorical and algebraic tools allows a more conceptual and insightful expression of elementary events such as measurements, teleportation and entanglement operations, that were obscured in previous formalisms.
An Introduction to Quantum Computing, Without the Physics
Nannicini, Giacomo
2017-01-01
This paper is a gentle but rigorous introduction to quantum computing intended for discrete mathematicians. Starting from a small set of assumptions on the behavior of quantum computing devices, we analyze their main characteristics, stressing the differences with classical computers, and finally describe two well-known algorithms (Simon's algorithm and Grover's algorithm) using the formalism developed in previous sections. This paper does not touch on the physics of the devices, and therefor...
Physical approach to quantum networks with massive particles
Andersen, Molte Emil Strange; Zinner, Nikolaj Thomas
2018-04-01
Assembling large-scale quantum networks is a key goal of modern physics research with applications in quantum information and computation. Quantum wires and waveguides in which massive particles propagate in tailored confinement is one promising platform for realizing a quantum network. In the literature, such networks are often treated as quantum graphs, that is, the wave functions are taken to live on graphs of one-dimensional edges meeting in vertices. Hitherto, it has been unclear what boundary conditions on the vertices produce the physical states one finds in nature. This paper treats a quantum network from a physical approach, explicitly finds the physical eigenstates and compares them to the quantum-graph description. The basic building block of a quantum network is an X-shaped potential well made by crossing two quantum wires, and we consider a massive particle in such an X well. The system is analyzed using a variational method based on an expansion into modes with fast convergence and it provides a very clear intuition for the physics of the problem. The particle is found to have a ground state that is exponentially localized to the center of the X well, and the other symmetric solutions are formed so to be orthogonal to the ground state. This is in contrast to the predictions of the conventionally used so-called Kirchoff boundary conditions in quantum graph theory that predict a different sequence of symmetric solutions that cannot be physically realized. Numerical methods have previously been the only source of information on the ground-state wave function and our results provide a different perspective with strong analytical insights. The ground-state wave function has a spatial profile that looks very similar to the shape of a solitonic solution to a nonlinear Schrödinger equation, enabling an analytical prediction of the wave number. When combining multiple X wells into a network or grid, each site supports a solitonlike localized state. These
Scattering theory in quantum mechanics. Physical principles and mathematical methods
International Nuclear Information System (INIS)
Amrein, W.O.; Jauch, J.M.; Sinha, K.B.
1977-01-01
A contemporary approach is given to the classical topics of physics. The purpose is to explain the basic physical concepts of quantum scattering theory, to develop the necessary mathematical tools for their description, to display the interrelation between the three methods (the Schroedinger equation solutions, stationary scattering theory, and time dependence) to derive the properties of various quantities of physical interest with mathematically rigorous methods
Understanding quantum physics; Verstehen in der Quantenphysik
Energy Technology Data Exchange (ETDEWEB)
Spillner, Vera
2011-07-01
This thesis presents a bundle definition for 'scientific understanding' through which the empirically equivalent interpretations of quantum mechanics can be evaluated with respect to the understanding they generate. The definition of understanding is based on a sufficient and necessary criterion, as well as a bundle of conditions - where a theory can be called most understandable whenever it fulfills the highest number of bundle criteria. Thereby the definition of understanding is based on the one hand on the objective number of criteria a theory fulfills, as well as, on the other hand, on the individual's preference of bundle criteria. Applying the definition onto three interpretations of quantum mechanics, the interpretation of David Bohm appears as most understandable, followed by the interpretation of Tim Maudlin and the Kopenhagen interpretation. These three interpretations are discussed in length in my thesis. (orig.)
Quantum Manybody Physics with Rydberg Polaritons
2016-06-22
otherwise induce eddy currents in the piezos and shake the resonator). It appears likely that the technology will also find application in LIGO, as...new type of synthetic material was designed, built, and tested , and a complete framework for engineering Hamiltonians developed. We built a machine ...with a collection of information if it does not display a currently valid OMB control number. 22-06-2016 Final 03-27-2013 - 03-31-2016 Quantum Manybody
Synthesis of quantum chromodynamics and nuclear physics
International Nuclear Information System (INIS)
Brodsky, S.J.; Lepage, G.P.
1980-08-01
The asymptotic freedom behavior of quantum chromodynamics allows the rigorous calculation of hadronic and nuclear amplitudes at short distances by perturbative methods. The implications of QCD for large-momentum-transfer nuclear form factors and scattering processes, as well as for the structure of nuclear wave functions and nuclear interactions at short distances, are discussed. The necessity for color-polarized internal nuclear states is also discussed. 6 figures
Theoretical physics IV. Quantum mechanics with problems in MAPLE
International Nuclear Information System (INIS)
Reinecker, Peter; Schulz, Michael; Schulz, Beatrix M.
2008-01-01
Quantum mechanics 2 is the fourth volume of the new and unique series for theoretical physics with Maple applications. This from basics newly concipated series mediates theoretical physics from contemporary view and in a way referring to a comprehensive lecture experience. Extensively and completely in five consecutively appearing volumes classical mechanics, electrodynamics, quantum mechanics 1 and 2, as well as statistical physics and thermodynamics are presented. Additionally for the elegant and extensive presentation on an each added CP applications for MAPLE trademark are contained, the software, which at more and more university is already applied in the lecture. They allow the experimenting with theory - and facilitate the understanding essentially. The present volume mediates extending, more complex contents of quantum mechanics, which are based on volume III of the series
Early germs of quantum field theory in the history of quantum physics
International Nuclear Information System (INIS)
Hund, F.
1983-01-01
The main concepts of quantum electrodynamics: duality of fields and particles, field quanta, antiparticles, creation and annihilation of particles, reactions based on a coupling, these concepts are common for all quantum field theory. Roots and germs of them we find already in the early history of quantum physics. Up to creation and physical understanding of quantum mechanics (1927) we can distinguish three steps. The first, ranging from black body radiation to specific heat (1900-1913) was essentially low temperature physics; h became the natural unity for counting cases in statistics. The second step was search for atomic mechanics (19131925): it was guided by a special law of atomic spectra, the combination principle ν=F (n,1...) - F (n',1'...); The third step (1923-1927), De Broglie's transfer of duality from light to matter, Schrodinger's equation, the concept of probability amplitudes, led to a general mathematical formalism and its physical understanding. During the first of these historical steps duality of light was detected and a sort of quantization of the light field took place; during the second step this duality remained in the background; during the third step duality of light and matter were seen as the center of quantum physics
Computational Physics Simulation of Classical and Quantum Systems
Scherer, Philipp O. J
2010-01-01
This book encapsulates the coverage for a two-semester course in computational physics. The first part introduces the basic numerical methods while omitting mathematical proofs but demonstrating the algorithms by way of numerous computer experiments. The second part specializes in simulation of classical and quantum systems with instructive examples spanning many fields in physics, from a classical rotor to a quantum bit. All program examples are realized as Java applets ready to run in your browser and do not require any programming skills.
Randomness in quantum mechanics: philosophy, physics and technology
Nath Bera, Manabendra; Acín, Antonio; Kuś, Marek; Mitchell, Morgan W.; Lewenstein, Maciej
2017-12-01
This progress report covers recent developments in the area of quantum randomness, which is an extraordinarily interdisciplinary area that belongs not only to physics, but also to philosophy, mathematics, computer science, and technology. For this reason the article contains three parts that will be essentially devoted to different aspects of quantum randomness, and even directed, although not restricted, to various audiences: a philosophical part, a physical part, and a technological part. For these reasons the article is written on an elementary level, combining simple and non-technical descriptions with a concise review of more advanced results. In this way readers of various provenances will be able to gain while reading the article.
Randomness in quantum mechanics: philosophy, physics and technology.
Bera, Manabendra Nath; Acín, Antonio; Kuś, Marek; Mitchell, Morgan W; Lewenstein, Maciej
2017-12-01
This progress report covers recent developments in the area of quantum randomness, which is an extraordinarily interdisciplinary area that belongs not only to physics, but also to philosophy, mathematics, computer science, and technology. For this reason the article contains three parts that will be essentially devoted to different aspects of quantum randomness, and even directed, although not restricted, to various audiences: a philosophical part, a physical part, and a technological part. For these reasons the article is written on an elementary level, combining simple and non-technical descriptions with a concise review of more advanced results. In this way readers of various provenances will be able to gain while reading the article.
Computational physics. Simulation of classical and quantum systems
Energy Technology Data Exchange (ETDEWEB)
Scherer, Philipp O.J. [TU Muenchen (Germany). Physikdepartment T38
2010-07-01
This book encapsulates the coverage for a two-semester course in computational physics. The first part introduces the basic numerical methods while omitting mathematical proofs but demonstrating the algorithms by way of numerous computer experiments. The second part specializes in simulation of classical and quantum systems with instructive examples spanning many fields in physics, from a classical rotor to a quantum bit. All program examples are realized as Java applets ready to run in your browser and do not require any programming skills. (orig.)
Imagery, intuition and imagination in quantum physics education
Stapleton, Andrew J.
2018-03-01
In response to the authors, I demonstrate how threshold concepts offer a means to both contextualise teaching and learning of quantum physics and help transform students into the culture of physics, and as a way to identify particularly troublesome concepts within quantum physics. By drawing parallels from my own doctoral research in another area of contemporary physics—special relativity—I highlight concepts that require an ontological change, namely a shift beyond the reality of everyday Newtonian experience such as time dilation and length contraction, as being troublesome concepts that can present barriers to learning with students often asking "is it real?". Similarly, the domain of quantum physics requires students to move beyond "common sense" perception as it brings into sharp focus the difference between what is experienced via the sense perceptions and the mental abstraction of phenomena. And it's this issue that highlights the important role imagery and creativity have both in quantum physics and in the evolution of physics more generally, and lies in stark contrast to the apparent mathematical focus and lack of opportunity for students to explore ontological issues evident in the authors' research. By reflecting on the authors' observations of a focus on mathematical formalisms and problem solving at the expense of alternative approaches, I explore the dialectic between Heisenberg's highly mathematical approach and Schrödinger's mechanical wave view of the atom, together with its conceptual imagery, at the heart of the evolution of quantum mechanics. In turn, I highlight the significance of imagery, imagination and intuition in quantum physics, together with the importance of adopting an epistemological pluralism—multiple ways of knowing and thinking—in physics education. Again drawing parallels with the authors' work and my own, I identify the role thought experiments have in both quantum physics education and in physics more generally. By
Aquilanti, Vincenzo; Bitencourt, Ana Carla P.; Ferreira, Cristiane da S.; Marzuoli, Annalisa; Ragni, Mirco
2008-11-01
The mathematical apparatus of quantum-mechanical angular momentum (re)coupling, developed originally to describe spectroscopic phenomena in atomic, molecular, optical and nuclear physics, is embedded in modern algebraic settings which emphasize the underlying combinatorial aspects. SU(2) recoupling theory, involving Wigner's 3nj symbols, as well as the related problems of their calculations, general properties, asymptotic limits for large entries, nowadays plays a prominent role also in quantum gravity and quantum computing applications. We refer to the ingredients of this theory—and of its extension to other Lie and quantum groups—by using the collective term of 'spin networks'. Recent progress is recorded about the already established connections with the mathematical theory of discrete orthogonal polynomials (the so-called Askey scheme), providing powerful tools based on asymptotic expansions, which correspond on the physical side to various levels of semi-classical limits. These results are useful not only in theoretical molecular physics but also in motivating algorithms for the computationally demanding problems of molecular dynamics and chemical reaction theory, where large angular momenta are typically involved. As for quantum chemistry, applications of these techniques include selection and classification of complete orthogonal basis sets in atomic and molecular problems, either in configuration space (Sturmian orbitals) or in momentum space. In this paper, we list and discuss some aspects of these developments—such as for instance the hyperquantization algorithm—as well as a few applications to quantum gravity and topology, thus providing evidence of a unifying background structure.
Physics Colloquium: The optical route to quantum information processing
Université de Genève
2011-01-01
Geneva University Physics Department 24, Quai Ernest Ansermet CH-1211 Geneva 4 Monday 11 April 2011 17h00 - Ecole de Physique, Auditoire Stückelberg The optical route to quantum information processing Prof. Terry Rudolph/Imperial College, London Photons are attractive as carriers of quantum information both because they travel, and can thus transmit information, but also because of their good coherence properties and ease in undergoing single-qubit manipulations. The main obstacle to their use in information processing is inducing an effective interaction between them in order to produce entanglement. The most promising approach in photon-based information processing architectures is so-called measurement-based quantum computing. This relies on creating upfront a multi-qubit highly entangled state (the cluster state) which has the remarkable property that, once prepared, it can be used to perform quantum computation by making only single qubit measurements. In this talk I will discuss generically the...
Hamiltonian and physical Hilbert space in polymer quantum mechanics
International Nuclear Information System (INIS)
Corichi, Alejandro; Vukasinac, Tatjana; Zapata, Jose A
2007-01-01
In this paper, a version of polymer quantum mechanics, which is inspired by loop quantum gravity, is considered and shown to be equivalent, in a precise sense, to the standard, experimentally tested Schroedinger quantum mechanics. The kinematical cornerstone of our framework is the so-called polymer representation of the Heisenberg-Weyl (HW) algebra, which is the starting point of the construction. The dynamics is constructed as a continuum limit of effective theories characterized by a scale, and requires a renormalization of the inner product. The result is a physical Hilbert space in which the continuum Hamiltonian can be represented and that is unitarily equivalent to the Schroedinger representation of quantum mechanics. As a concrete implementation of our formalism, the simple harmonic oscillator is fully developed
The Oxford Questions on the foundations of quantum physics
Briggs, G. A. D.; Butterfield, J. N.; Zeilinger, A.
2013-01-01
The twentieth century saw two fundamental revolutions in physics—relativity and quantum. Daily use of these theories can numb the sense of wonder at their immense empirical success. Does their instrumental effectiveness stand on the rock of secure concepts or the sand of unresolved fundamentals? Does measuring a quantum system probe, or even create, reality or merely change belief? Must relativity and quantum theory just coexist or might we find a new theory which unifies the two? To bring such questions into sharper focus, we convened a conference on Quantum Physics and the Nature of Reality. Some issues remain as controversial as ever, but some are being nudged by theory's secret weapon of experiment. PMID:24062626
The geometric phase in quantum physics
International Nuclear Information System (INIS)
Bohm, A.
1993-03-01
After an explanatory introduction, a quantum system in a classical time-dependent environment is discussed; an example is a magnetic moment in a classical magnetic field. At first, the general abelian case is discussed in the adiabatic approximation. Then the geometric phase for nonadiabatic change of the environment (Anandan--Aharonov phase) is introduced, and after that general cyclic (nonadiabatic) evolution is discussed. The mathematics of fiber bundles is introduced, and some of its results are used to describe the relation between the adiabatic Berry phase and the geometric phase for general cyclic evolution of a pure state. The discussion is restricted to the abelian, U(1) phase
Quantum Processes and Dynamic Networks in Physical and Biological Systems.
Dudziak, Martin Joseph
Quantum theory since its earliest formulations in the Copenhagen Interpretation has been difficult to integrate with general relativity and with classical Newtonian physics. There has been traditionally a regard for quantum phenomena as being a limiting case for a natural order that is fundamentally classical except for microscopic extrema where quantum mechanics must be applied, more as a mathematical reconciliation rather than as a description and explanation. Macroscopic sciences including the study of biological neural networks, cellular energy transports and the broad field of non-linear and chaotic systems point to a quantum dimension extending across all scales of measurement and encompassing all of Nature as a fundamentally quantum universe. Theory and observation lead to a number of hypotheses all of which point to dynamic, evolving networks of fundamental or elementary processes as the underlying logico-physical structure (manifestation) in Nature and a strongly quantized dimension to macroscalar processes such as are found in biological, ecological and social systems. The fundamental thesis advanced and presented herein is that quantum phenomena may be the direct consequence of a universe built not from objects and substance but from interacting, interdependent processes collectively operating as sets and networks, giving rise to systems that on microcosmic or macroscopic scales function wholistically and organically, exhibiting non-locality and other non -classical phenomena. The argument is made that such effects as non-locality are not aberrations or departures from the norm but ordinary consequences of the process-network dynamics of Nature. Quantum processes are taken to be the fundamental action-events within Nature; rather than being the exception quantum theory is the rule. The argument is also presented that the study of quantum physics could benefit from the study of selective higher-scale complex systems, such as neural processes in the brain
International Nuclear Information System (INIS)
Huebel, Horst
2010-01-01
Traditionally in the center of interest on quantum physics referring to schools the question lies, whether electrons and photons are now particles or waves, a question, which is often characterized by the phrase ''wave-particle dualism'', which notoriously not exists in its original meaning. Against that by the author - basing on important preparatory works of Kueblbeck and Mueller - a new concept for the treatment of quantum physics for the school was proposed, which puts ''basic facts'' in the foreground, comparable with the Kueblbeck-Mueller ''characteristic features''. The ''basic facts'' are similar to axioms of quantum physics, by means of which a large number of experiments and phenomena can be ''explained'' at least qualitatively - in a heuristic way -. Instead of the so-called ''wave-particle dualism'' here uncertainty and complementarity are put in the foreground. The new concept is in the Internet under http://www.forphys.de extensively presented with many further materials. In the partial volumes of this publication manifold and carefully elaborated teaching materials are presented, by means of which scholars can get themselves the partial set of quantum physics referring to schools by different methods like learn at stations, short referates, Internet research, group puzzle, the query-sheet or the card-index method etc. In the present 2. part materials for the ''basic facts'' of quantum physics are prepared, by which also modern experiments can be interpreted. Here deals it with the getting of knowledge and application of the ''basic Facts''. This pursues also by real scholar experiments, simulations and analogy tests. The scholars obtain so more simply than generally a deeper insight in quantum physics.
Quantum readout of physical unclonable functions
Skoric, B.
2012-01-01
Physical unclonable functions (PUFs) are physical structures that are hard to clone and have a unique challenge-response behavior. The term PUF was coined by Pappu et al. in 2001. That work triggered a lot of interest, and since then a substantial number of papers has been written about the use of a
Teaching Einsteinian Physics at Schools: Part 2, Models and Analogies for Quantum Physics
Kaur, Tejinder; Blair, David; Moschilla, John; Zadnik, Marjan
2017-01-01
The Einstein-First project approaches the teaching of Einsteinian physics through the use of physical models and analogies. This paper presents an approach to the teaching of quantum physics which begins by emphasising the particle-nature of light through the use of toy projectiles to represent photons. This allows key concepts including the…
Theoretical physics 7 quantum mechanics : methods and applications
Nolting, Wolfgang
2017-01-01
This textbook offers a clear and comprehensive introduction to methods and applications in quantum mechanics, one of the core components of undergraduate physics courses. It follows on naturally from the previous volumes in this series, thus developing the understanding of quantized states further on. The first part of the book introduces the quantum theory of angular momentum and approximation methods. More complex themes are covered in the second part of the book, which describes multiple particle systems and scattering theory. Ideally suited to undergraduate students with some grounding in the basics of quantum mechanics, the book is enhanced throughout with learning features such as boxed inserts and chapter summaries, with key mathematical derivations highlighted to aid understanding. The text is supported by numerous worked examples and end of chapter problem sets. About the Theoretical Physics series Translated from the renowned and highly successful German editions, the eight volumes of this seri...
The infamous boundary seven decades of controversy in quantum physics
Wick, David
1995-01-01
reprinted in the British trade journal Physics World in 1990, three separate and 5 lengthy replies from establishment physicists were printed in subsequent issues. For outsiders, especially scientists who rely on physicist's theories in their own fields, this situation is disquieting. Moreover, many recall their introduction to quantum mechanics as a startling, if not shocking, experience. A molecular biologist related how he had started in theoretical physics but, after hearing the ideology of quantum mechanics, marched straight to the Reg istrar's office and switched fields. A colleague recalled how her undergraduate chemistry professor religiously entertained queries from the class - until one day he began with the words: "No questions will be permitted on today's lecture." The topic, of course, was quantum mechanics. My father, an organic chemist at a Midwestern university, also had to give that dreaded annual lecture. Around age 16, I picked up a little book he used to prepare and was perplexed by the ...
International Nuclear Information System (INIS)
Corradini, Antonella; Meixner, Uwe
2014-01-01
Quantum physics, in contrast to classical physics, allows non-locality and indeterminism in nature. Moreover, the role of the observer seems indispensable in quantum physics. In fact, quantum physics, unlike classical physics, suggests a metaphysics that is not physicalism (which is today's official metaphysical doctrine). As is well known, physicalism implies a reductive position in the philosophy of mind, specifically in its two core areas, the philosophy of consciousness and the philosophy of action. Quantum physics, in contrast, is compatible with psychological non-reductionism, and actually seems to support it. The essays in this book explore, from various points of view, the possibilities of basing a non-reductive philosophy of mind on quantum physics. In doing so, they not only engage with the ontological and epistemological aspects of the question but also with the neurophysiological ones.
Energy Technology Data Exchange (ETDEWEB)
Corradini, Antonella [Catholic Univ., Milan (Italy); Meixner, Uwe (ed.) [Augsburg Univ. (Germany)
2014-07-01
Quantum physics, in contrast to classical physics, allows non-locality and indeterminism in nature. Moreover, the role of the observer seems indispensable in quantum physics. In fact, quantum physics, unlike classical physics, suggests a metaphysics that is not physicalism (which is today's official metaphysical doctrine). As is well known, physicalism implies a reductive position in the philosophy of mind, specifically in its two core areas, the philosophy of consciousness and the philosophy of action. Quantum physics, in contrast, is compatible with psychological non-reductionism, and actually seems to support it. The essays in this book explore, from various points of view, the possibilities of basing a non-reductive philosophy of mind on quantum physics. In doing so, they not only engage with the ontological and epistemological aspects of the question but also with the neurophysiological ones.
Principles of physics from quantum field theory to classical mechanics
Jun, Ni
2014-01-01
This book starts from a set of common basic principles to establish the formalisms in all areas of fundamental physics, including quantum field theory, quantum mechanics, statistical mechanics, thermodynamics, general relativity, electromagnetic field, and classical mechanics. Instead of the traditional pedagogic way, the author arranges the subjects and formalisms in a logical-sequential way, i.e. all the formulas are derived from the formulas before them. The formalisms are also kept self-contained. Most of the required mathematical tools are also given in the appendices. Although this book covers all the disciplines of fundamental physics, the book is concise and can be treated as an integrated entity. This is consistent with the aphorism that simplicity is beauty, unification is beauty, and thus physics is beauty. The book may be used as an advanced textbook by graduate students. It is also suitable for physicists who wish to have an overview of fundamental physics. Readership: This is an advanced gradua...
Quantum Physics and Mental Health Counseling: The Time Is...!
Gerstein, Lawrence H.; Bennett, Matt
1999-01-01
Introduces a new framework of mental health counseling based on quantum physics. The framework stresses systemic thinking and intervention, interdependence, and the importance of adopting a novel perspective about time, space, reality, and change. This framework has the potential of modifying mental health counseling practice and training. Offers…
Quantum algebras and Poisson geometry in mathematical physics
Karasev, M V
2005-01-01
This collection presents new and interesting applications of Poisson geometry to some fundamental well-known problems in mathematical physics. The methods used by the authors include, in addition to advanced Poisson geometry, unexpected algebras with non-Lie commutation relations, nontrivial (quantum) Kählerian structures of hypergeometric type, dynamical systems theory, semiclassical asymptotics, etc.
A Quantum Chemistry Concept Inventory for Physical Chemistry Classes
Dick-Perez, Marilu; Luxford, Cynthia J.; Windus, Theresa L.; Holme, Thomas
2016-01-01
A 14-item, multiple-choice diagnostic assessment tool, the quantum chemistry concept inventory or QCCI, is presented. Items were developed based on published student misconceptions and content coverage and then piloted and used in advanced physical chemistry undergraduate courses. In addition to the instrument itself, data from both a pretest,…
Infinite dimensional groups and algebras in quantum physics
International Nuclear Information System (INIS)
Ottesen, J.T.
1995-01-01
This book is an introduction to the application of infite-dimensional groups and algebras in quantum physics. Especially considered are the spin representation of the infinite-dimensional orthogonal group, the metaplectic representation of the infinite-dimensional symplectic groups, and Loop and Virasoro algebras. (HSI)
Physical states in Quantum Einstein-Cartan Gravity
Cianfrani, Francesco
2016-01-01
The definition of physical states is the main technical issue of canonical approaches towards Quantum Gravity. In this work, we outline how those states can be found in Einstein-Cartan theory via a continuum limit and they are given by finite dimensional representations of the Lorentz group.
Effective Hamiltonians in quantum physics: resonances and geometric phase
International Nuclear Information System (INIS)
Rau, A R P; Uskov, D
2006-01-01
Effective Hamiltonians are often used in quantum physics, both in time-dependent and time-independent contexts. Analogies are drawn between the two usages, the discussion framed particularly for the geometric phase of a time-dependent Hamiltonian and for resonances as stationary states of a time-independent Hamiltonian
Uniqueness of inverse scattering problem in local quantum physics
Energy Technology Data Exchange (ETDEWEB)
Schroer, Bert [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)]. E-mail: schroer@cbpf.br
2001-06-01
It is shown that the a Bisognano-Wichmann-Unruh inspired formulation of local quantum physics which starts from wedge-localized algebras, leads to a uniqueness proof for the scattering problem. The important mathematical tool is the thermal KMS aspect of localization and its strengthening by the requirement of crossing symmetry for generalized formfactors. (author)
From quantum fields to fractal structures: intermittency in particle physics
International Nuclear Information System (INIS)
Peschanski, R.
1991-01-01
Some features and theoretical interpretations of the intermittency phenomenon observed in high-energy multi-particle production are recalled. One develops on the various connections found with fractal structuration of fluctuations in turbulence, spin-glass physics and aggregation phenomena described by the non-linear Smoluchowski equation. This may lead to a new approach to quantum field properties
International Nuclear Information System (INIS)
Schroer, Bert; Freie Universitaet, Berlin
2003-05-01
After recalling episodes from Pascual Jordan's biography including his pivotal role in the shaping of quantum field theory and his much criticized conduct during the NS regime, I draw attention to his presentation of the first phase of development of quantum field theory in a talk presented at the 1929 Kharkov conference. He starts by giving a comprehensive account of the beginnings of quantum theory, emphasising that particle-like properties arise as a consequence of treating wave-motions quantum-mechanically. He then goes on to his recent discovery of quantization of 'wave fields' and problems of gauge invariance. The most surprising aspect of Jordan's presentation is however his strong belief that his field quantization is a transitory not yet optimal formulation of the principles underlying causal, local quantum physics. The expectation of a future more radical change coming from the main architect of field quantization already shortly after his discovery is certainly quite startling. I try to answer the question to what extent Jordan's 1929 expectations have been vindicated. The larger part of the present essay consists in arguing that Jordan's plea for a formulation without 'classical correspondence crutches', i.e. for an intrinsic approach (which avoids classical fields altogether), is successfully addressed in past and recent publications on local quantum physics. (author)
Edge physics of the quantum spin Hall insulator from a quantum dot excited by optical absorption.
Vasseur, Romain; Moore, Joel E
2014-04-11
The gapless edge modes of the quantum spin Hall insulator form a helical liquid in which the direction of motion along the edge is determined by the spin orientation of the electrons. In order to probe the Luttinger liquid physics of these edge states and their interaction with a magnetic (Kondo) impurity, we consider a setup where the helical liquid is tunnel coupled to a semiconductor quantum dot that is excited by optical absorption, thereby inducing an effective quantum quench of the tunneling. At low energy, the absorption spectrum is dominated by a power-law singularity. The corresponding exponent is directly related to the interaction strength (Luttinger parameter) and can be computed exactly using boundary conformal field theory thanks to the unique nature of the quantum spin Hall edge.
Foundations of quantum mechanics an exploration of the physical meaning of quantum theory
Norsen, Travis
2017-01-01
Authored by an acclaimed teacher of quantum physics and philosophy, this textbook pays special attention to the aspects that many courses sweep under the carpet. Traditional courses in quantum mechanics teach students how to use the quantum formalism to make calculations. But even the best students - indeed, especially the best students - emerge rather confused about what, exactly, the theory says is going on, physically, in microscopic systems. This supplementary textbook is designed to help such students understand that they are not alone in their confusions (luminaries such as Albert Einstein, Erwin Schroedinger, and John Stewart Bell having shared them), to sharpen their understanding of the most important difficulties associated with interpreting quantum theory in a realistic manner, and to introduce them to the most promising attempts to formulate the theory in a way that is physically clear and coherent. The text is acces sible to students with at least one semester of prior exposure to quantum (or...
The Groenewold-Moyal Plane and its Quantum Physics
International Nuclear Information System (INIS)
Balachandran, A. P.; Padmanabhan, Pramod
2009-01-01
Quantum theories constructed on the noncommutative spacetime called the Groenewold-Moyal(GM) plane exhibit many interesting properties such as causality violation, Lorentz and CPT non-invariance and twisted statistics. Such violations lead to many striking features that may be tested experimentally. Thus these theories predict Pauli-forbidden transitions due to twisted statistics, anisotropies and acausal effects in the cosmic microwave background radiation in correlations of observables and Lorentz and CPT violations in scattering amplitudes. Such features of quantum physics on the GM plane are surveyed in this review.
Large numbers hypothesis. IV - The cosmological constant and quantum physics
Adams, P. J.
1983-01-01
In standard physics quantum field theory is based on a flat vacuum space-time. This quantum field theory predicts a nonzero cosmological constant. Hence the gravitational field equations do not admit a flat vacuum space-time. This dilemma is resolved using the units covariant gravitational field equations. This paper shows that the field equations admit a flat vacuum space-time with nonzero cosmological constant if and only if the canonical LNH is valid. This allows an interpretation of the LNH phenomena in terms of a time-dependent vacuum state. If this is correct then the cosmological constant must be positive.
Lie algebra in quantum physics by means of computer algebra
Kikuchi, Ichio; Kikuchi, Akihito
2017-01-01
This article explains how to apply the computer algebra package GAP (www.gap-system.org) in the computation of the problems in quantum physics, in which the application of Lie algebra is necessary. The article contains several exemplary computations which readers would follow in the desktop PC: such as, the brief review of elementary ideas of Lie algebra, the angular momentum in quantum mechanics, the quark eight-fold way model, and the usage of Weyl character formula (in order to construct w...
Thirty years that shook physics the story of quantum theory
Gamow, George A
1966-01-01
""Dr. Gamow, physicist and gifted writer, has sketched an intriguing portrait of the scientists and clashing ideas that made the quantum revolution."" - Christian Science MonitorIn 1900, German physicist Max Planck postulated that light, or radiant energy, can exist only in the form of discrete packages or quanta. This profound insight, along with Einstein's equally momentous theories of relativity, completely revolutionized man's view of matter, energy, and the nature of physics itself.In this lucid layman's introduction to quantum theory, an eminent physicist and noted popularizer of scien
Limited entropic uncertainty as new principle of quantum physics
International Nuclear Information System (INIS)
Ion, D.B.; Ion, M.L.
2001-01-01
The Uncertainty Principle (UP) of quantum mechanics discovered by Heisenberg, which constitute the corner-stone of quantum physics, asserts that: there is an irreducible lower bound on the uncertainty in the result of a simultaneous measurement of non-commuting observables. In order to avoid this state-dependence many authors proposed to use the information entropy as a measure of the uncertainty instead of above standard quantitative formulation of the Heisenberg uncertainty principle. In this paper the Principle of Limited Entropic Uncertainty (LEU-Principle), as a new principle in quantum physics, is proved. Then, consistent experimental tests of the LEU-principle, obtained by using the available 49 sets of the pion-nucleus phase shifts, are presented for both, extensive (q=1) and nonextensive (q=0.5 and q=2.0) cases. Some results obtained by the application of LEU-Principle to the diffraction phenomena are also discussed. The main results and conclusions of our paper can be summarized as follows: (i) We introduced a new principle in quantum physics namely the Principle of Limited Entropic Uncertainty (LEU-Principle). This new principle includes in a more general and exact form not only the old Heisenberg uncertainty principle but also introduce an upper limit on the magnitude of the uncertainty in the quantum physics. The LEU-Principle asserts that: 'there is an irreducible lower bound as well as an upper bound on the uncertainty in the result of a simultaneous measurement of non-commuting observables for any extensive and nonextensive (q ≥ 0) quantum systems'; (ii) Two important concrete realizations of the LEU-Principle are explicitly obtained in this paper, namely: (a) the LEU-inequalities for the quantum scattering of spinless particles and (b) the LEU-inequalities for the diffraction on single slit of width 2a. In particular from our general results, in the limit y → +1 we recover in an exact form all the results previously reported. In our paper an
Being qua becoming: Aristotle's "Metaphysics", quantum physics, and Process Philosophy
Johnson, David Kelley
In Aristotle's First Philosophy, science and philosophy were partners, but with the rise of empiricism, went their separate ways. Metaphysics combined the rational and irrational (i.e. final cause/unmoved mover) elements of existence to equate being with substance, postulating prime matter as pure potential that was actuated by form to create everything. Modern science reveres pure reason and postulates its theory of being by a rigorous scientific methodology. The Standard Model defines matter as energy formed into fundamental particles via forces contained in fields. Science has proved Aristotle's universe wrong in many ways, but as physics delves deeper into the quantum world, empiricism is reaching its limits concerning fundamental questions of existence. To achieve its avowed mission of explaining existence completely, physics must reunite with philosophy in a metascience modeled on the First Philosophy of Aristotle. One theory of being that integrates quantum physics and metaphysics is Process Philosophy.
The pivotal role of causality in local quantum physics
International Nuclear Information System (INIS)
Schroer, Bert
1999-04-01
In this article an attempt is made to present very recent conceptual and computational developments in QFT as new manifestation of old well established physical principles. The vehicle for converting the quantum-algebraic aspects of local quantum physics into more classical geometric structures is the modular theory of Tomita. As the above named laureate together with his collaborator showed for the first time, in sufficient generality, its use in physics goes through Einstein causality. This line of research recently gained momentum when it was realized that it is not only of great structural and conceptual innovative power (see section 4), but also promises a new computational road into nonperturbative QFT (section 5) which, picturesquely speaking, enters the subject on the extreme opposite (noncommutative) side relative to (Lagrangian) quantization. (author)
Barnes, Marianne B.; Garner, James; Reid, David
2004-01-01
In this article we use the pendulum as the vehicle for discussing the transition from classical to quantum physics. Since student knowledge of the classical pendulum can be generalized to all harmonic oscillators, we propose that a quantum analysis of the pendulum can lead students into the unanticipated consequences of quantum phenomena at the…
Beyond quantum probability: another formalism shared by quantum physics and psychology.
Dzhafarov, Ehtibar N; Kujala, Janne V
2013-06-01
There is another meeting place for quantum physics and psychology, both within and outside of cognitive modeling. In physics it is known as the issue of classical (probabilistic) determinism, and in psychology it is known as the issue of selective influences. The formalisms independently developed in the two areas for dealing with these issues turn out to be identical, opening ways for mutually beneficial interactions.
Bøe, Maria Vetleseter; Henriksen, Ellen Karoline; Angell, Carl
2018-01-01
Calls for renewal of physics education include more varied learning activities and increased focus on qualitative understanding and history and philosophy of science (HPS) aspects. We have studied an innovative approach implementing such features in quantum physics in traditional upper secondary physics classrooms in Norway. Data consists of 11…
Logical reformulation of quantum mechanics. IV. Projectors in semiclassical physics
International Nuclear Information System (INIS)
Omnes, R.
1989-01-01
This is a technical paper providing the proofs of three useful theorems playing a central role in two kinds of physical applications: an explicit logical and mathematical formulation of the interpretation of quantum mechanics and the corresponding description of irreversibility. The Appendix contains a brief mathematical introduction to microlocal analysis. Three theorems are derived in the text: (A) Associating a projector in Hilbert space with a macroscopic regular cell in classical phase space. (B) Specifying the algebra of the projectors associated with different cells. (C) Showing the connection between the classical motion of cells and the Schroedinger evolution of projectors for a class of regular Hamiltonians corresponding approximately to deterministic systems as described within the framework of quantum mechanics. Applications to the interpretation of quantum mechanics are given and the consequences for irreversibility will be given later
The Device-Independent Outlook On Quantum Physics
International Nuclear Information System (INIS)
Scarani, V.
2012-01-01
This text is an introduction to an operational outlook on Bell inequalities, which has been very fruitful in the past few years. It has lead to the recognition that Bell tests have their own place in applied quantum technologies, because they quantify non-classicality in a device-independent way, that is, without any need to describe the degrees of freedom under study and the measurements that are performed. At the more fundamental level, the same device-independent outlook has allowed the falsification of several other alternative models that could hope to reproduce the observed statistics while keeping some classical features that quantum theory denies; and it has shed new light on the long-standing quest for deriving quantum theory from physical principles. (author)
Cybernetical Physics From Control of Chaos to Quantum Control
Fradkov, Alexander L
2007-01-01
The control of complex systems is one of the most important aspects in dealing with systems exhibiting nonlinear behaviour or similar features that defy traditional control techniques. This specific subject is gradually becoming known as cybernetical physics, borrowing methods from both theoretical physics and control engineering. This book is, perhaps, the first attempt to present a unified exposition of the subject and methodology of cybernetical physics as well as solutions to some of its problems. Emphasis of the book is on the examination of fundamental limits on energy transformation by means of control procedures in both conservative and dissipative systems. A survey of application in physics includes the control of chaos, synchronisation of coupled oscillators, pendulum chains, reactions in physical chemistry and of quantum systems such as the dissociation of diatomic molecules. This book has been written having researchers from various backgrounds in physics, mathematics and engineering in mind and i...
Quantum mechanics. Textbook on theoretical physics III. 4. rev. ed.
International Nuclear Information System (INIS)
Fliessbach, T.
2005-01-01
This textbook present an intoduction to quantum mechanics, as it is offerred at the university in the cycle ''Theoretical Physics''. Special value has the author put on a well readable, understandable, and surveyable representation, so that the reader it can reproduce without larger difficulties. By the partition into chapters, which form separated course units, and the kind of the representation the book is also suited for bachelor curricula. The quantum mechanics are first introduced in the form of Schroedinge's wave mechanics. The fundamental relations of quantum mechanics and their interpretation are thereby explained by means of examples and first applications. In the following chapters the most important applications of the Schroedinger equation are studied, like the alpha decay, the scattering of a particle on a potential, and the hydrogen atom. Thereafter the abstract formulation of quantum mechanics (Hilbert space) is introduced in analogy to the known structure of the vector space. This formulation is then applied to concrete problems like the oscillator, tha angular momentum, and the spin. The most important approximation methods of quantum mechanics are then summarized. In the concluding part about many-particle systems the ideal Fermi gas is treated; simple applications of this model in atomic, solid-state, nuclear, ans astrophysics are discussed
Basic quantum theory and measurement from the viewpoint of local quantum physics
International Nuclear Information System (INIS)
Schroer, Bert
1999-04-01
Several aspects of the manifestation of the causality principle in LQP (local quantum physics) are reviewed or presented. Particular emphasis is given to those properties which are typical for LQP in the sense that they do go beyond the structure of general quantum theory and even escape the Lagrangian quantization methods of standard QFT. The most remarkable are those relating causality to the modular Tomita-Takesaki theory, since they bring in the basic concepts of antiparticles, charge superselections as well as internal and external (geometric and hidden) symmetries. (author)
Tales of the quantum understanding physics' most fundamental theory
Hobson, Art
2017-01-01
Everybody has heard that we live in a world made of atoms. But far more fundamentally, we live in a universe made of quanta. Many things are not made of atoms: light, radio waves, electric current, magnetic fields, Earth's gravitational field, not to mention exotica such a neutron stars, black holes, dark energy, and dark matter. But everything, including atoms, is made of highly unified or "coherent" bundles of energy called "quanta" that (like everything else) obey certain rules. In the case of the quantum, these rules are called "quantum physics." This is a book about quanta and their unexpected, some would say peculiar, behavior--tales, if you will, of the quantum. The quantum has developed the reputation of being capricious, bewildering, even impossible to understand. The peculiar habits of quanta are certainly not what we would have expected to find at the foundation of physical reality, but these habits are not necessarily bewildering and not at all impossible or paradoxical. This book explains those h...
Quantum Dot Semiconductor Optical Amplifiers - Physics and Applications
DEFF Research Database (Denmark)
Berg, Tommy Winther
2004-01-01
This thesis describes the physics and applications of quantum dot semiconductor optical amplifiers based on numerical simulations. These devices possess a number of unique properties compared with other types of semiconductor amplifiers, which should allow enhanced performance of semiconductor...... respects is comparable to those of fiber amplifiers. The possibility of inverting the optically active states to a large degree is essential in order to achieve this performance. Optical signal processing through cross gain modulation and four wave mixing is modeled and described. For both approaches...... and QW devices and to experiments on quantum dot amplifiers. These comparisons outline the qualitative differences between the different types of amplifiers. In all cases focus is put on the physical processes responsible the differences....
Semiotic aspects of quantum physics; Semiotische Aspekte der Quantenphysik
Energy Technology Data Exchange (ETDEWEB)
Januschke, Eugen
2010-07-01
By means of semiotics it is studied, how it succeeds in quantum physics to make formulas plausible, the basic physical facts of which are not accessible for a common understanding respectively an understanding in the sense of classical physics. Thereby it deals with a generally acknowledged kind of making understandable of certain physical formulas beyond the individual marking distinctly of abilities of explaining and understanding of social phenomena and historical developments, whereby to these formulas each a certain experiment is put on side. The experiment is thereby such chosen that the physical phenomenon, which is described in the formula, is studied in the experiment, so that the formula then results as evaluation of the experiment.
Franceschetti, Donald R; Gire, Elizabeth
2013-06-01
Quantum probability theory offers a viable alternative to classical probability, although there are some ambiguities inherent in transferring the quantum formalism to a less determined realm. A number of physicists are now looking at the applicability of quantum ideas to the assessment of physics learning, an area particularly suited to quantum probability ideas.
Quantum physics, relativity and complex spacetime towards a new synthesis
Kaiser, Gerald
1990-01-01
A new synthesis of the principles of quantum mechanics and Relativity is proposed in the context of complex differential geometry. The positivity of the energy implies that wave functions and fields can be extended to complex spacetime, and it is shown that this complexification has a solid physical interpretation as an extended phase space. The extended fields can be said to be realistic wavelet transforms of the original fields. A new, algebraic theory of wavelets is developed.
Two-dimensional Ising physics in quantum Hall ferromagnets
Czech Academy of Sciences Publication Activity Database
Jungwirth, Tomáš; MacDonald, A. H.; Rezayi, E. H.
2002-01-01
Roč. 12, - (2002), s. 1-7 ISSN 1386-9477 R&D Projects: GA ČR GA202/01/0754; GA MŠk OC 514.10 Institutional research plan: CEZ:AV0Z1010914 Keywords : quantum Hall ferromagnets * higher Landau levels * domain walls Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.107, year: 2002
From quantum physics to consciousness. Cosmos, spirit, and matter
International Nuclear Information System (INIS)
Goernitz, Thomas; Goernitz, Brigitte
2016-01-01
The present book is a consequent continuation and deepening of a new concept layed down ba Thomas and Brigitte Goernitz in several writings. Starting from quantum theory they describe the evolution of the spirituality from the origin of the cosmos until the origin of the consciousness. Obtained was this knowledge by profund physical and mathematical research lasting for decades and in cooperation lasting for years with scientists and philosophers, especially with Carl Friedrich v. Weizsaecker.
Outline of a classical theory of quantum physics and gravitation
International Nuclear Information System (INIS)
Gallop, J.W.
1975-01-01
It is argued that in the manner in which the Galilean-Newtonian physics may be said to have explained the Ptolemaic-Copernican theories in terms which have since been called classical, so also Milner's theories of the structure of matter may be said to explain present day quantum and relativistic theory. In both cases the former employ the concept of force and the latter, by contrast, are geometrical theories. Milner envisaged space as being stressed, whereas Einstein thought of it as strained. Development of Milner's theory from criticisms and suggestions made by Kilmister has taken it further into the realms of quantum and gravitational physics, where it is found to give a more physically comprehensible explanation of the phenomena. Further, it shows why present day quantum theory is cast in a statistical form. The theory is supported by many predictions such as the ratio of Planck's constant to the mass of the electron, the value of the fine structure constant and reason for apparent variations in past measurements, the magnetic moment of the electron and proton of the stable particles such as the neutron Λ and Σ together with the kaon, and a relation between the universal gravitational constant and Hubble's constant - all within published experimental accuracy. The latest results to be accounted for by the theory are the masses of the newly discovered psi particles and confirmation of the value of the decay of Newton's gravitational constant obtained from lunar measurements. (author)
A proposed physical analog for a quantum probability amplitude
Boyd, Jeffrey
What is the physical analog of a probability amplitude? All quantum mathematics, including quantum information, is built on amplitudes. Every other science uses probabilities; QM alone uses their square root. Why? This question has been asked for a century, but no one previously has proposed an answer. We will present cylindrical helices moving toward a particle source, which particles follow backwards. Consider Feynman's book QED. He speaks of amplitudes moving through space like the hand of a spinning clock. His hand is a complex vector. It traces a cylindrical helix in Cartesian space. The Theory of Elementary Waves changes direction so Feynman's clock faces move toward the particle source. Particles follow amplitudes (quantum waves) backwards. This contradicts wave particle duality. We will present empirical evidence that wave particle duality is wrong about the direction of particles versus waves. This involves a paradigm shift; which are always controversial. We believe that our model is the ONLY proposal ever made for the physical foundations of probability amplitudes. We will show that our ``probability amplitudes'' in physical nature form a Hilbert vector space with adjoints, an inner product and support both linear algebra and Dirac notation.
International Nuclear Information System (INIS)
Rebhan, E.
2005-01-01
The present second volume treats quantum mechanics, relativistic quantum mechanics, the foundations of quantum-field and elementary-particle theory as well as thermodynamics and statistics. Both volumes comprehend all fields, which are usually offered in a course about theoretical physics. In all treated fields a very careful introduction to the basic natural laws forms the starting point, whereby it is thoroughly analysed, which of them is based on empirics, which is logically deducible, and which role play basic definitions. Extendingly the matter extend of the corresponding courses starting from the relativistic quantum theory an introduction to the elementary particles is developed. All problems are very thoroughly and such extensively studied, that each step is singularly reproducible. On motivation and good understandability is cared much about. The mixing of mathematical difficulties with problems of physical nature often obstructive in the learning is so circumvented, that important mathematical methods are presented in own chapters (for instance Hilbert spaces, Lie groups). By means of many examples and problems (for a large part with solutions) the matter worked out is deepened and exercised. Developments, which are indeed important, but seem for the first approach abandonable, are pursued in excurses. This book starts from courses, which the author has held at the Heinrich-Heine university in Duesseldorf, and was in many repetitions fitted to the requirements of the students. It is conceived in such a way, that it is also after the study suited as dictionary or for the regeneration
Al-Khalili, Jim
2003-01-01
In this lively look at quantum science, a physicist takes you on an entertaining and enlightening journey through the basics of subatomic physics. Along the way, he examines the paradox of quantum mechanics--beautifully mathematical in theory but confoundingly unpredictable in the real world. Marvel at the Dual Slit experiment as a tiny atom passes through two separate openings at the same time. Ponder the peculiar communication of quantum particles, which can remain in touch no matter how far apart. Join the genius jewel thief as he carries out a quantum measurement on a diamond without ever touching the object in question. Baffle yourself with the bizzareness of quantum tunneling, the equivalent of traveling partway up a hill, only to disappear then reappear traveling down the opposite side. With its clean, colorful layout and conversational tone, this text will hook you into the conundrum that is quantum mechanics.
Quantum mechanics. Textbook on Theoretical Physics III. 5. ed.
International Nuclear Information System (INIS)
Fliessbach, Torsten
2008-01-01
This textbook gives an introduction to quantum mechanics, as it is presented at the university in the cycle ''Theoretical Physics''. Special care has the author put om a well readable, understandable, and clearly arranged presentation, so that the reader can it reproduce without greater difficulties. By the partition into chapters, which form self-contained teaching units, and the kind of presentation the book is also very well suited for bachelor courses. Quantum mechanics is first introduced in form of Schroedinger's wave mechanics. The fundamental relations and their interpretation are thereby explained hand in hand with examples and first applications. In the following parts the most important applications of the Schroedinger equation are studied, as the alpha decay, the scattering of particles on a potential, and the hydrogen atom. Thereafter the abstract formulation of quantum mechanics (Hilbert space) is introduced in analogy to the known structure of the vector space. This formulation is applied to concrete problems, as the oscillator, the angular momentum, and the spin. The most important approximation methods of quantum mechanics are then summarized. In the final part about many-particle systems the ideal Fermi gas is treated; simple application of this model in atomic, solid-state,and astrophysics are discussed
Fundamentals of physics II electromagnetism, optics, and quantum mechanics
Shankar, R
2016-01-01
R. Shankar, a well-known physicist and contagiously enthusiastic educator, was among the first to offer a course through the innovative Open Yale Course program. His popular online video lectures on introductory physics have been viewed over a million times. In this second book based on his online Yale course, Shankar explains essential concepts, including electromagnetism, optics, and quantum mechanics. The book begins at the simplest level, develops the basics, and reinforces fundamentals, ensuring a solid foundation in the principles and methods of physics. It provides an ideal introduction for college-level students of physics, chemistry, and engineering; for motivated AP Physics students; and for general readers interested in advances in the sciences.
International Nuclear Information System (INIS)
Enders, P.
2006-01-01
This book goes a novel way from classical physics to quantum physics. After the description of Euler's and Helmholtz's representations of classical mechanics the Schroedinger equation is derivated without making any additional assumptions about the nature of quantum mechanical systems. Thereby not the differences between but the common properties of classical and quantum mechanics are accentuated and four fundamental problems of the quantization named by Schroedinger are solved. Extensively to the historical literature is related. This book applies not only to students and scientists but also to teachers and historians of natural sciences: It contains many details which enter no more into modern presentations of classical mechanics, but are important for the understanding of quantum mechanics [de
Quantum cloning machines and their implementation in physical systems
International Nuclear Information System (INIS)
Wu Tao; Ye Liu; Fang Bao-Long
2013-01-01
We review the basic theory of approximate quantum cloning for discrete variables and some schemes for implementing quantum cloning machines. Several types of approximate quantum clones and their expansive quantum clones are introduced. As for the implementation of quantum cloning machines, we review some design methods and recent experimental results. (topical review - quantum information)
Quantum many-body physics in a nutshell
Shuryak, Edward
2018-01-01
This book provides an essential introduction to the physics of quantum many-body systems, which are at the heart of atomic and nuclear physics, condensed matter, and particle physics. Unlike other textbooks on the subject, it covers topics across a broad range of physical fields―phenomena as well as theoretical tools―and does so in a simple and accessible way. Edward Shuryak begins with Feynman diagrams of the quantum and statistical mechanics of a particle―in these applications, the diagrams are easy to calculate and there are no divergencies. He discusses the renormalization group and illustrates its uses and covers systems such as weakly and strongly coupled Bose and Fermi gases, electron gas, nuclear matter, and quark-gluon plasmas. Phenomena include Bose condensation and superfluidity. Shuryak also looks at Cooper pairing and superconductivity for electrons in metals, liquid 3He, nuclear matter, and quark-gluon plasma. A recurring topic throughout is topological matter, ranging from ensembles of q...
Energy Technology Data Exchange (ETDEWEB)
Friege, Gunnar; Scholz, Ruediger (eds.)
2017-07-01
In this book aids for the instruction of quantum physics are described. Especially considered are the conception of the photon, quantum interference, entanglement, the photoelectric effect, and coincidence experiments. (HSI)
Andreev reflections and the quantum physics of black holes
Manikandan, Sreenath K.; Jordan, Andrew N.
2017-12-01
We establish an analogy between superconductor-metal interfaces and the quantum physics of a black hole, using the proximity effect. We show that the metal-superconductor interface can be thought of as an event horizon and Andreev reflection from the interface is analogous to the Hawking radiation in black holes. We describe quantum information transfer in Andreev reflection with a final state projection model similar to the Horowitz-Maldacena model for black hole evaporation. We also propose the Andreev reflection analogue of Hayden and Preskill's description of a black hole final state, where the black hole is described as an information mirror. The analogy between crossed Andreev reflections and Einstein-Rosen bridges is discussed: our proposal gives a precise mechanism for the apparent loss of quantum information in a black hole by the process of nonlocal Andreev reflection, transferring the quantum information through a wormhole and into another universe. Given these established connections, we conjecture that the final quantum state of a black hole is exactly the same as the ground state wave function of the superconductor/superfluid in the Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity; in particular, the infalling matter and the infalling Hawking quanta, described in the Horowitz-Maldacena model, forms a Cooper pairlike singlet state inside the black hole. A black hole evaporating and shrinking in size can be thought of as the analogue of Andreev reflection by a hole where the superconductor loses a Cooper pair. Our model does not suffer from the black hole information problem since Andreev reflection is unitary. We also relate the thermodynamic properties of a black hole to that of a superconductor, and propose an experiment which can demonstrate the negative specific heat feature of black holes in a growing/evaporating condensate.
Unitary quantum physics with time-space non-commutativity
International Nuclear Information System (INIS)
Balachandran, A P; Govindarajan, T R; Martins, A G; Molina, C; Teotonio-Sobrinho, P
2005-01-01
In these lectures 4 quantum physics in noncommutative spacetime is developed. It is based on the work of Doplicher et al. which allows for time-space noncommutativity. In the context of noncommutative quantum mechanics, some important points are explored, such as the formal construction of the theory, symmetries, causality, simultaneity and observables. The dynamics generated by a noncommutative Schroedinger equation is studied. The theory is further extended to certain noncommutative versions of the cylinder, R 3 and R x S 3 . In all these models, only discrete time translations are possible. One striking consequence of quantised time translations is that even though a time independent Hamiltonian is an observable, in scattering processes, it is conserved only modulo 2π/θ, where θ is the noncommutative parameter. Scattering theory is formulated and an approach to quantumfield theory is outlined
Physics on all scales. Scalar-tensor theories of quantum gravity in particle physics and cosmology
Energy Technology Data Exchange (ETDEWEB)
Henz, Tobias
2016-05-10
In this thesis, we investigate dilaton quantum gravity using a functional renormalization group approach. We derive and discuss flow equations both in the background field approximation and using a vertex expansion as well as solve the fixed point equations globally to show how realistic gravity, connecting ultraviolet and infrared physics, can be realized on a pure fixed point trajectory by virtue of spontaneous breaking of scale invariance. The emerging physical system features a dynamically generated moving Planck scale resembling the Newton coupling as well as slow roll inflation with an exponentially decreasing effective cosmological constant that vanishes completely in the infrared. The moving Planck scale might make quantum gravity experimentally accessible at a different energy scale than previously believed. We therefore not only provide further evidence for the existence of a consistent quantum theory of gravity based on general relativity, but also offer potential solutions towards the hierarchy and cosmological constant problems, thereby opening up exciting opportunities for further research.
Becchi, Carlo Maria
2016-01-01
This is the third edition of a well-received textbook on modern physics theory. This book provides an elementary but rigorous and self-contained presentation of the simplest theoretical framework that will meet the needs of undergraduate students. In addition, a number of examples of relevant applications and an appropriate list of solved problems are provided.Apart from a substantial extension of the proposed problems, the new edition provides more detailed discussion on Lorentz transformations and their group properties, a deeper treatment of quantum mechanics in a central potential, and a closer comparison of statistical mechanics in classical and in quantum physics. The first part of the book is devoted to special relativity, with a particular focus on space-time relativity and relativistic kinematics. The second part deals with Schrödinger's formulation of quantum mechanics. The presentation concerns mainly one-dimensional problems, but some three-dimensional examples are discussed in detail. The third...
Scholar-activating teaching materials on quantum physics. Pt. 3. Foundations of atomic physics
International Nuclear Information System (INIS)
Huebel, Horst
2010-01-01
Traditionally in the center of the interest on quantum physics referring to schools the question lies, whether electrons or photons are now particles or waves, a question, which is often characterized by the phrase ''wave-particle dualism'', which notoriously not exists in its original meaning. Against that by the author - on the base of important preparatory works of Kueblbeck and Mueller - a new concept of quantum physics for the school was proposed, which puts ''basic facts'' in the foreground, comparable with the Kueblbeck-Mueller ''characteristic features''. The ''basic facts'' are similar to axioms of quantum physics, by means of them a large number of experiments and phenomena can be ''explained'' at least qualitatively - in a heuristic way -. Instead of the so-called ''wave-particle dualism'' uncertainty and complementarity are put in the foreground. The new concept is in the Internet under http://www.forphys.de extensively presented with many further materials. In the partial volumes of this publication manifold and carefully elaborated teaching materials are presented, by which scholars can get themselves the partial set of quantum physics referring to schools by different methods like learning at stations, short referates, Internet-research, group puzzle, the query-sheet or the card-index method etc. In the present 3. part materials are prepared, by which scholars can get foundations of atomic physics and interpret in the sense of the ''basic facts or quantum physics''. Here deals it thus with discrete energy levels, the linear potential box, with atomic models, the atomic structure, the tunnel effect, and - because curricula it often require - also with the Schroedinger equation. The materials can also be usefully applied in other concepts.
Computational physics simulation of classical and quantum systems
Scherer, Philipp O J
2013-01-01
This textbook presents basic and advanced computational physics in a very didactic style. It contains very-well-presented and simple mathematical descriptions of many of the most important algorithms used in computational physics. Many clear mathematical descriptions of important techniques in computational physics are given. The first part of the book discusses the basic numerical methods. A large number of exercises and computer experiments allows to study the properties of these methods. The second part concentrates on simulation of classical and quantum systems. It uses a rather general concept for the equation of motion which can be applied to ordinary and partial differential equations. Several classes of integration methods are discussed including not only the standard Euler and Runge Kutta method but also multistep methods and the class of Verlet methods which is introduced by studying the motion in Liouville space. Besides the classical methods, inverse interpolation is discussed, together with the p...
Majorana Fermions in Particle Physics, Solid State and Quantum Information
Borsten, L.; Duff, M. J.
This review is based on lectures given by M. J. Duff summarising the far reaching contributions of Ettore Majorana to fundamental physics, with special focus on Majorana fermions in all their guises. The theoretical discovery of the eponymous fcrmion in 1937 has since had profound implications for particlc physics, solid state and quantum computation. The breadth of these disciplines is testimony to Majorana's genius, which continues to permeate physics today. These lectures offer a whistle-stop tour through some limited subset of the key ideas. In addition to touching on these various applications, we will draw out some fascinating relations connecting the normed division algebras R, ℂ, H, O to spinors, trialities. K-theory and the classification of stable topological states of symmetry-protected gapped free-fermion systems.
How to upload a physical quantum state into correlation space
International Nuclear Information System (INIS)
Morimae, Tomoyuki
2011-01-01
In the framework of the computational tensor network [Phys. Rev. Lett. 98, 220503 (2007)], the quantum computation is performed in a virtual linear space called the correlation space. It was recently shown [Phys. Rev. Lett. 103, 050503 (2009)] that a state in a correlation space can be downloaded to the real physical space. In this paper, conversely, we study how to upload a state from a real physical space to the correlation space. After showing the impossibility of cloning a state between a real physical space and the correlation space, we propose a simple teleportation-like method of uploading. This method also enables the Gottesman-Chuang gate teleportation trick and entanglement swapping in the virtual-real hybrid setting. Furthermore, compared with the inverse of the downloading method by Cai et al. [Phys. Rev. Lett. 103, 050503 (2009)], which also works to upload, the proposed uploading method has several advantages.
Physics of frequency-modulated comb generation in quantum-well diode lasers
Dong, Mark; Cundiff, Steven T.; Winful, Herbert G.
2018-05-01
We investigate the physical origin of frequency-modulated combs generated from single-section semiconductor diode lasers based on quantum wells, isolating the essential physics necessary for comb generation. We find that the two effects necessary for comb generation—spatial hole burning (leading to multimode operation) and four-wave mixing (leading to phase locking)—are indeed present in some quantum-well systems. The physics of comb generation in quantum wells is similar to that in quantum dot and quantum cascade lasers. We discuss the nature of the spectral phase and some important material parameters of these diode lasers.
The cosmic code quantum physics as the language of nature
Pagels, Heinz R
2012-01-01
""The Cosmic Code can be read by anyone. I heartily recommend it!"" - The New York Times Book Review""A reliable guide for the nonmathematical reader across the highest ridges of physical theory. Pagels is unfailingly lighthearted and confident."" - Scientific American""A sound, clear, vital work that deserves the attention of anyone who takes an interest in the relationship between material reality and the human mind."" - Science 82This is one of the most important books on quantum mechanics ever written for general readers. Heinz Pagels, an eminent physicist and science writer, discusses and
Theoretical physics 3. Quantum mechanics 1 with problems in MAPLE
International Nuclear Information System (INIS)
Reineker, P.; Schulz, M.; Schulz, B.M.
2007-01-01
The following topics are dealt with: Historically heuristic introduction to quantum mechanics, the Schroedinger equation, foundations of quantum mechanics, the linear harmonic oscillator, quantum-mechanical motion in the central field, approximation methods for the solution of quantum mechanical problems, motion of particles in the electromagnetic field, spin and magnetic moment of the electron, many-particle systems, conceptional problems of quantum mechanics
Tomonaga-Luttinger physics in electronic quantum circuits.
Jezouin, S; Albert, M; Parmentier, F D; Anthore, A; Gennser, U; Cavanna, A; Safi, I; Pierre, F
2013-01-01
In one-dimensional conductors, interactions result in correlated electronic systems. At low energy, a hallmark signature of the so-called Tomonaga-Luttinger liquids is the universal conductance curve predicted in presence of an impurity. A seemingly different topic is the quantum laws of electricity, when distinct quantum conductors are assembled in a circuit. In particular, the conductances are suppressed at low energy, a phenomenon called dynamical Coulomb blockade. Here we investigate the conductance of mesoscopic circuits constituted by a short single-channel quantum conductor in series with a resistance, and demonstrate a proposed link to Tomonaga-Luttinger physics. We reformulate and establish experimentally a recently derived phenomenological expression for the conductance using a wide range of circuits, including carbon nanotube data obtained elsewhere. By confronting both conductance data and phenomenological expression with the universal Tomonaga-Luttinger conductance curve, we demonstrate experimentally the predicted mapping between dynamical Coulomb blockade and the transport across a Tomonaga-Luttinger liquid with an impurity.
15th International Conference on Non-Hermitian Hamiltonians in Quantum Physics
Passante, Roberto; Trapani, Camillo
2016-01-01
This book presents the Proceedings of the 15th International Conference on Non-Hermitian Hamiltonians in Quantum Physics, held in Palermo, Italy, from 18 to 23 May 2015. Non-Hermitian operators, and non-Hermitian Hamiltonians in particular, have recently received considerable attention from both the mathematics and physics communities. There has been a growing interest in non-Hermitian Hamiltonians in quantum physics since the discovery that PT-symmetric Hamiltonians can have a real spectrum and thus a physical relevance. The main subjects considered in this book include: PT-symmetry in quantum physics, PT-optics, Spectral singularities and spectral techniques, Indefinite-metric theories, Open quantum systems, Krein space methods, and Biorthogonal systems and applications. The book also provides a summary of recent advances in pseudo-Hermitian Hamiltonians and PT-symmetric Hamiltonians, as well as their applications in quantum physics and in the theory of open quantum systems.
Causal ubiquity in quantum physics a superluminal and local-causal physical ontology
Neelamkavil, Raphael
2014-01-01
A fixed highest criterial velocity (of light) in STR (special theory of relativity) is a convention for a layer of physical inquiry. QM (Quantum Mechanics) avoids action-at-a-distance using this concept, but accepts non-causality and action-at-a-distance in EPR (Einstein-Podolsky-Rosen-Paradox) entanglement experiments. Even in such allegedly non-causal processes, something exists processually in extension-motion, between the causal and the non-causal. If STR theoretically allows real-valued superluminal communication between EPR entangled particles, quantum processes become fully causal. That
Blanchard, Philippe
2015-01-01
The second edition of this textbook presents the basic mathematical knowledge and skills that are needed for courses on modern theoretical physics, such as those on quantum mechanics, classical and quantum field theory, and related areas. The authors stress that learning mathematical physics is not a passive process and include numerous detailed proofs, examples, and over 200 exercises, as well as hints linking mathematical concepts and results to the relevant physical concepts and theories. All of the material from the first edition has been updated, and five new chapters have been added on such topics as distributions, Hilbert space operators, and variational methods. The text is divided into three main parts. Part I is a brief introduction to distribution theory, in which elements from the theories of ultradistributions and hyperfunctions are considered in addition to some deeper results for Schwartz distributions, thus providing a comprehensive introduction to the theory of generalized functions. P...
A Synthetic Approach to the Transfer Matrix Method in Classical and Quantum Physics
Pujol, O.; Perez, J. P.
2007-01-01
The aim of this paper is to propose a synthetic approach to the transfer matrix method in classical and quantum physics. This method is an efficient tool to deal with complicated physical systems of practical importance in geometrical light or charged particle optics, classical electronics, mechanics, electromagnetics and quantum physics. Teaching…
Quantum physics in the nanoworld Schrödinger's cat and the dwarfs
Lüth, Hans
2015-01-01
The second edition deals with all essential aspects of non-relativistic quantum physics up to the quantisation of fields. In contrast to common textbooks of quantum mechanics, modern experiments are described both for the purpose of foundation of the theory and in relation to recent applications. Links are made to important research fields and applications such as elementary particle physics, solid state physics and nuclear magnetic resonance in medicine, biology and material science. Special emphasis is paid to quantum physics in nanoelectronics such as resonant tunnelling, Coulomb blockade and the realisation of quantum bits. This second edition also considers quantum transport through quantum point contacts and its application as charge detectors in nanoelectronic circuits. Also the realization and the study of electronic properties of an artificial quantum dot molecule are presented. Because of its recent interest a brief discussion of Bose-Einstein condensation has been included, as well as the rece...
Freedom and the psychoanalytic ontology of quantum physics.
Gullatz, Stefan; Gildersleeve, Matthew
2018-02-01
Jung's paper 'Synchronicity - an acausal connecting principle', defining the phenomenon as a 'meaningful' coincidence depending on archetypal activation, was published in 1952, together with a conceptually related piece by physicist and Nobel Laureate Wolfgang Pauli entitled, 'The influence of archetypal ideas on the scientific theories of Kepler'. Slavoj Žižek, in The Indivisible Remainder: On Schelling and Related Matters, suggests that, in contrast to any notion of a 'pre-modern Jungian harmony', the main lesson of quantum physics was that not only was the psychoanalytic, empty subject of the signifier constitutively out-of-joint with respect to the world, but that the Real in itself was already incomplete, out-of-joint, 'not-all'. Yet while Žižek frequently tries to separate Jung from his own ontology, this paper shows that his ontology is not as different as he suggests. Consistent with our earlier publications on Jung and Zizek, a closer investigation reveals an underlying congruence of both of their approaches. In this paper we show that this affinity lies in the rejection by both Jung and Žižek of the ideology of reductive materialism, a rejection that demonstrably draws on quantum physics in similar ways. While Jung posits an inherently meaningful universe, Žižek attempts to salvage the freedom of human subjectivity by opposing his Lacanian 'dialectical materialism' to reductive materialism. © 2018, The Society of Analytical Psychology.
Physical renormalization schemes and asymptotic safety in quantum gravity
Falls, Kevin
2017-12-01
The methods of the renormalization group and the ɛ -expansion are applied to quantum gravity revealing the existence of an asymptotically safe fixed point in spacetime dimensions higher than two. To facilitate this, physical renormalization schemes are exploited where the renormalization group flow equations take a form which is independent of the parameterisation of the physical degrees of freedom (i.e. the gauge fixing condition and the choice of field variables). Instead the flow equation depends on the anomalous dimensions of reference observables. In the presence of spacetime boundaries we find that the required balance between the Einstein-Hilbert action and Gibbons-Hawking-York boundary term is preserved by the beta functions. Exploiting the ɛ -expansion near two dimensions we consider Einstein gravity coupled to matter. Scheme independence is generically obscured by the loop-expansion due to breaking of two-dimensional Weyl invariance. In schemes which preserve two-dimensional Weyl invariance we avoid the loop expansion and find a unique ultraviolet (UV) fixed point. At this fixed point the anomalous dimensions are large and one must resum all loop orders to obtain the critical exponents. Performing the resummation a set of universal scaling dimensions are found. These scaling dimensions show that only a finite number of matter interactions are relevant. This is a strong indication that quantum gravity is renormalizable.
Quantum Physics in high school: a bakhtinian analysis of Physics textbooks approved at PNLDEM 2015
Directory of Open Access Journals (Sweden)
Nathan Willig Lima
2017-08-01
Full Text Available In this work we present an analysis of Quantum Physics texts present in the fourteen books approved by the National Textbook Plan for High School in 2015. We used Bakhtin’s Philosophy of Language as a theoretical and methodological framework. Our aim was to evaluate which approaches are used by textbook authors to introduce Quantum Physics as well as which concepts and epistemological views are stated in these presentations. Our results show that all books present a historical approach, limited to the Old Quantum Physics. Concepts and presentation sequences are very similar to what can be found in Modern Physics undergraduate textbooks, containing even the same historiographic mistakes. This suggests that authors state what they have learned during undergraduate courses without any further critical review. All books present lexical choice that can be associated to positivist epistemology, and thirteen books present a compositional structure allied to the same view, which is considered epistemologically outdated. The reductionist textbook presentation indicates the necessity of breaking up with the hegemonic positivist perspective.
International Nuclear Information System (INIS)
Ivanov, V.V.
2003-01-01
The present collection of letters from JINR, Dubna, contains ten separate records on the microscopic entropy and nonlocality, conditional density matrix: systems and subsystems in quantum mechanics, physics of quantum computation, flipping qubits, quantum zeno effect for N-level Friedrichs model, universal hybrid quantum processors, formation of the SU(3)-polarization states in atom-quantum electromagnetic field system under condition of the Bose-Einstein condensate existence, periodical sequences (trajectories) of outcomes of atomic state measurement on exit from the micromaser cavity, an algebraic method to solve the Tavis-Cummings problem, quantum teleportation of nuclear matter and its investigation
Numerical perturbative methods in the quantum theory of physical systems
International Nuclear Information System (INIS)
Adam, G.
1980-01-01
During the last two decades, development of digital electronic computers has led to the deployment of new, distinct methods in theoretical physics. These methods, based on the advances of modern numerical analysis as well as on specific equations describing physical processes, enabled to perform precise calculations of high complexity which have completed and sometimes changed our image of many physical phenomena. Our efforts have concentrated on the development of numerical methods with such intrinsic performances as to allow a successful approach of some Key issues in present theoretical physics on smaller computation systems. The basic principle of such methods is to translate, in numerical analysis language, the theory of perturbations which is suited to numerical rather than to analytical computation. This idea has been illustrated by working out two problems which arise from the time independent Schroedinger equation in the non-relativistic approximation, within both quantum systems with a small number of particles and systems with a large number of particles, respectively. In the first case, we are led to the numerical solution of some quadratic ordinary differential equations (first section of the thesis) and in the second case, to the solution of some secular equations in the Brillouin area (second section). (author)
Energy Technology Data Exchange (ETDEWEB)
Huebel, Horst
2008-07-01
Traditionally in the interest on quantum physics referring to school the question holds the spotlight, whether electrons of photons are now particles ore waves, a formulation of the question, which is often characterized by the phrase ''Wave-particle dualism'', which as is known not exists in its original meaning. Contrarily by the author - starting from important preparations of Kueblbeck and Mueller - a new concept for the treatment of quantum physics for the school is proposed, which puts fundamental facts in the foreground, comparable with Kueblbeck-Mueller's ''Wesenzuege''. The fundamental facts are similar to axioms of quantum physics, by means of which a large number of experiments and phenomena of quantum physics can at least qualitatively - in a heuristic way - be explained. Instead of the mentioned wave-particle dualism here undeterminism and complementarity are put in the foreground. The new concept is in the internet extensively presented under http://www.forphys.de with may further materials. In the partial volumes of this publication manifold and carefully elaborated instructional materials are presented, by which the scholars can themselves elaborate the partial set of quantum physics referred to school by different methods like learning at stations, short referates, internet research, group puzzle, the query-sheet or the card-index method etc. In the present 1. part materials for prestages of quantum physics are provided, so to interference trials, which-way experiments, trials on the particle conception of quantum theory, on photons, and on Planck's action quantum. A section is also dedicated to the so-called ''model-philosophy'' as preliminary interpretation of quantum physics, which corresponds more to tradiational ways of proceeding.
International Nuclear Information System (INIS)
Arndt, M.; Aspelmeyer, M.; Brukner, C.; Weihs, G.; Jennewein, T.; Schmiedmayer, J.; Weinfurter, H.; Zukowski, M.
2005-01-01
Quantum information processing and communication is one of the of the key research areas within the European community. Therefore these two events were dedicated to present the advances in this area. Papers dealing with topics such as atom-photon entanglement, matter waves and quantum gases, decoherence, photonic entanglement, solid state quantum physics, cooling and trapping of atoms and molecules, quantum communication, quantum computation, quantum information and quantum cryptography were addressed. (nevyjel)
Quantum simulations and many-body physics with light.
Noh, Changsuk; Angelakis, Dimitris G
2017-01-01
In this review we discuss the works in the area of quantum simulation and many-body physics with light, from the early proposals on equilibrium models to the more recent works in driven dissipative platforms. We start by describing the founding works on Jaynes-Cummings-Hubbard model and the corresponding photon-blockade induced Mott transitions and continue by discussing the proposals to simulate effective spin models and fractional quantum Hall states in coupled resonator arrays (CRAs). We also analyse the recent efforts to study out-of-equilibrium many-body effects using driven CRAs, including the predictions for photon fermionisation and crystallisation in driven rings of CRAs as well as other dynamical and transient phenomena. We try to summarise some of the relatively recent results predicting exotic phases such as super-solidity and Majorana like modes and then shift our attention to developments involving 1D nonlinear slow light setups. There the simulation of strongly correlated phases characterising Tonks-Girardeau gases, Luttinger liquids, and interacting relativistic fermionic models is described. We review the major theory results and also briefly outline recent developments in ongoing experimental efforts involving different platforms in circuit QED, photonic crystals and nanophotonic fibres interfaced with cold atoms.
QUANTUM PHYSICS and HUMAN RESOURCE MANAGEMENT – DEFINING THE FIELD
Directory of Open Access Journals (Sweden)
Andronicus TORP
2014-11-01
Full Text Available This paper argues that it is possible, based on the universal principles revealed by Quantum Physics, to construct an energetic profile of a human being, using the ElectroPhotonic Imaging/Gas Discharge Visualisation-camera, where different frequency domains are connected with different clusters of skills, competences, and qualities, and that the amplitude of the energy within these domains indicates how much the specific person manifests these skills, competences, and qualities. Furthermore, this measurement also indicates the persons stress and energy level. In this way it is possible to compare two or more people objectively and quantitatively, which may find use for example in a Recruitment and Selection situation.
Conceptual citation frequency - quantum mechanics and elementary particle physics
International Nuclear Information System (INIS)
Hurt, C.D.
1986-01-01
The differences in conceptual citation frequency are examined between quantum mechanics literature and elementary particle physics literature. Using a sample based on increments of 5 years, 7 contrast tests were generated over a literature period of 35 years. A Dunn planned comparison procedure indicated a statistical difference in years 5 and 10 but no differences were found in the remaining years. The results must be weighed against the time frames in which the literature was produced but clearly point to an initial difference in the two areas. Additional work is required to reevaluate the findings and to investigate the conceptual citation frequency issue further. The frequency distribution generated approximates a cumulative advantage process. (author)
The Quantum Mechanics Solver: How to Apply Quantum Theory to Modern Physics, 2nd edition
International Nuclear Information System (INIS)
Robbin, J M
2007-01-01
he hallmark of a good book of problems is that it allows you to become acquainted with an unfamiliar topic quickly and efficiently. The Quantum Mechanics Solver fits this description admirably. The book contains 27 problems based mainly on recent experimental developments, including neutrino oscillations, tests of Bell's inequality, Bose-Einstein condensates, and laser cooling and trapping of atoms, to name a few. Unlike many collections, in which problems are designed around a particular mathematical method, here each problem is devoted to a small group of phenomena or experiments. Most problems contain experimental data from the literature, and readers are asked to estimate parameters from the data, or compare theory to experiment, or both. Standard techniques (e.g., degenerate perturbation theory, addition of angular momentum, asymptotics of special functions) are introduced only as they are needed. The style is closer to a non-specialist seminar rather than an undergraduate lecture. The physical models are kept simple; the emphasis is on cultivating conceptual and qualitative understanding (although in many of the problems, the simple models fit the data quite well). Some less familiar theoretical techniques are introduced, e.g. a variational method for lower (not upper) bounds on ground-state energies for many-body systems with two-body interactions, which is then used to derive a surprisingly accurate relation between baryon and meson masses. The exposition is succinct but clear; the solutions can be read as worked examples if you don't want to do the problems yourself. Many problems have additional discussion on limitations and extensions of the theory, or further applications outside physics (e.g., the accuracy of GPS positioning in connection with atomic clocks; proton and ion tumor therapies in connection with the Bethe-Bloch formula for charged particles in solids). The problems use mainly non-relativistic quantum mechanics and are organised into three
Probing University Students' Pre-Knowledge in Quantum Physics with QPCS Survey
Asikainen, Mervi A.
2017-01-01
The study investigated the use of Quantum Physics Conceptual Survey (QPCS) in probing student understanding of quantum physics. Altogether 103 Finnish university students responded to QPCS. The mean scores of the student responses were calculated and the test was evaluated using common five indices: Item difficulty index, Item discrimination…
Quantum Humor: The Playful Side of Physics at Bohr's Institute for Theoretical Physics
Halpern, Paul
2012-09-01
From the 1930s to the 1950s, a period of pivotal developments in quantum, nuclear, and particle physics, physicists at Niels Bohr's Institute for Theoretical Physics in Copenhagen took time off from their research to write humorous articles, letters, and other works. Best known is the Blegdamsvej Faust, performed in April 1932 at the close of one of the Institute's annual conferences. I also focus on the Journal of Jocular Physics, a humorous tribute to Bohr published on the occasions of his 50th, 60th, and 70th birthdays in 1935, 1945, and 1955. Contributors included Léon Rosenfeld, Victor Weisskopf, George Gamow, Oskar Klein, and Hendrik Casimir. I examine their contributions along with letters and other writings to show that they offer a window into some issues in physics at the time, such as the interpretation of complementarity and the nature of the neutrino, as well as the politics of the period.
3 minutes to understand the 50 greatest theories of quantum physics
International Nuclear Information System (INIS)
Clegg, Brian; Ball, Philip; Clifford, Leon; Close, Frank; Hebden, Sophie; Hellemans, Alexander; Holgate, Sharon Ann; May, Andrew; Martinez, Rachel; Dubois, Richard
2015-01-01
This book aims at using 2 pages, 300 words and 1 image to explain each of the 50 most important theories of quantum physics. After a first part addressing the origins of the theory (Planck quanta, the photoelectric effect according to Einstein, the predictable Balmer series, the Bohr's atom, the wave/particle duality, the matter waves of De Broglie, the double quantum slit), the chapters address basic notions (quantum spin, matrix mechanics, Schroedinger's equation and cat, the Heisenberg uncertainty principle, the wave function reduction, the decoherence), light and matter physics, quantum effects and their interpretation, quantum entanglement, quantum applications, and quantum extremes. Each chapter proposes a glossary, a presentation of specific issues according to the adopted format, and a portrait of a scientist involved in the addressed topics (Niels Bohr, Erwin Schroedinger, Paul Dirac, David Bohm, John Bell, Brian Josephson, and Satyendra Nath Bose)
Workshop on quantum stochastic differential equations for the quantum simulation of physical systems
2016-09-22
that would be complimentary to the efforts at ARL. One the other hand, topological quantum field theories have a dual application to topological...Witten provided a path-integral definition of the Jones polynomial using a three-dimensional Chern-Simons quantum field theory (QFT) based on a non...topology, quantum field theory , quantum stochastic differential equations, quantum computing REPORT DOCUMENTATION PAGE 11. SPONSOR/MONITOR’S REPORT
Stern-Gerlach Experiments and Complex Numbers in Quantum Physics
Sivakumar, S.
2012-01-01
It is often stated that complex numbers are essential in quantum theory. In this article, the need for complex numbers in quantum theory is motivated using the results of tandem Stern-Gerlach experiments
Causal ubiquity in quantum physics. A superluminal and local-causal physical ontology
International Nuclear Information System (INIS)
Neelamkavil, Raphael
2014-01-01
A fixed highest criterial velocity (of light) in STR (special theory of relativity) is a convention for a layer of physical inquiry. QM (Quantum Mechanics) avoids action-at-a-distance using this concept, but accepts non-causality and action-at-a-distance in EPR (Einstein-Podolsky-Rosen-Paradox) entanglement experiments. Even in such allegedly [non-causal] processes, something exists processually in extension-motion, between the causal and the [non-causal]. If STR theoretically allows real-valued superluminal communication between EPR entangled particles, quantum processes become fully causal. That is, the QM world is sub-luminally, luminally and superluminally local-causal throughout, and the Law of Causality is ubiquitous in the micro-world. Thus, ''probabilistic causality'' is a merely epistemic term.
Causal ubiquity in quantum physics. A superluminal and local-causal physical ontology
Energy Technology Data Exchange (ETDEWEB)
Neelamkavil, Raphael
2014-07-01
A fixed highest criterial velocity (of light) in STR (special theory of relativity) is a convention for a layer of physical inquiry. QM (Quantum Mechanics) avoids action-at-a-distance using this concept, but accepts non-causality and action-at-a-distance in EPR (Einstein-Podolsky-Rosen-Paradox) entanglement experiments. Even in such allegedly [non-causal] processes, something exists processually in extension-motion, between the causal and the [non-causal]. If STR theoretically allows real-valued superluminal communication between EPR entangled particles, quantum processes become fully causal. That is, the QM world is sub-luminally, luminally and superluminally local-causal throughout, and the Law of Causality is ubiquitous in the micro-world. Thus, ''probabilistic causality'' is a merely epistemic term.
Becchi, Carlo Maria
2007-01-01
These notes are designed as a text book for a course on the Modern Physics Theory for undergraduate students. The purpose is providing a rigorous and self-contained presentation of the simplest theoretical framework using elementary mathematical tools. A number of examples of relevant applications and an appropriate list of exercises and answered questions are also given. The first part is devoted to Special Relativity concerning in particular space-time relativity and relativistic kinematics. The second part deals with Schroedinger's formulation of quantum mechanics. The presentation concerns mainly one dimensional problems, in particular tunnel effect, discrete energy levels and band spectra. The third part concerns the application of Gibbs statistical methods to quantum systems and in particular to Bose and Fermi gasses.
'Who Thinks Abstractly?': Quantum Theory and the Architecture of Physical Concepts
International Nuclear Information System (INIS)
Plotnitsky, Arkady
2011-01-01
Beginning with its introduction by W. Heisenberg, quantum mechanics was often seen as an overly abstract theory, mathematically and physically, vis-a-vis classical physics or relativity. This perception was amplified by the fact that, while the quantum-mechanical formalism provided effective predictive algorithms for the probabilistic predictions concerning quantum experiments, it appeared unable to describe, even by way idealization, quantum processes themselves in space and time, in the way classical mechanics or relativity did. The aim of the present paper is to reconsider the nature of mathematical and physical abstraction in modern physics by offering an analysis of the concept of ''physical fact'' and of the concept of 'physical concept', in part by following G. W. F. Hegel's and G. Deleuze's arguments concerning the nature of conceptual thinking. In classical physics, relativity, and quantum physics alike, I argue, physical concepts are defined by the following main features - 1) their multi-component multiplicity; 2) their essential relations to problems; 3) and the interactions between physical, mathematical, and philosophical components within each concept. It is the particular character of these interactions in quantum mechanics, as defined by its essentially predictive (rather than descriptive) nature, that distinguishes it from classical physics and relativity.
Quantum revolution. [Vol.] 2: QED: the jewel of physics
International Nuclear Information System (INIS)
Venkataraman, G.
1994-01-01
Events leading to the plague or crisis of infinities in the field of quantum mechanics are surveyed in brief. How that crisis was contained by formulation of quantum electrodynamics (QED) theory is narrated in this volume. Contributions of Tomanoga, Schwinger and Feynman to the QED theory are discussed. The story of quantum mechanics is brought up to fifties. (M.G.B.)
Scattering and structures. Essentials and analogies in quantum physics. 2. ed.
Energy Technology Data Exchange (ETDEWEB)
Povh, Bogdan [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Rosina, Mitja [Ljubljana Univ. (Slovenia). Dept. of Physics
2017-07-01
Quantum physics may appear complicated, especially if one forgets the ''big picture'' and gets lost in the details. However, it can become clearer and less tangled if one applies a few fundamental concepts so that simplified approaches can emerge and estimated orders of magnitude become clear. Povh and Rosina's Scattering and Structures presents the properties of quantum systems (elementary particles, nucleons, atoms, molecules, quantum gases, quantum liquids, stars, and early universe) with the help of elementary concepts and analogies between these seemingly different systems. In this new edition, sections on quantum gases and an up to date overview of elementary particles have been added.
International Nuclear Information System (INIS)
Hueffel, H.
2004-01-01
The new seminar series 'Vienna central European seminar on particle physics and quantum field theory' has been created 2004 and is intended to provide interactions between leading researchers and junior physicists. This year 'Advances in quantum field theory' has been chosen as subject and is centred on field theoretic aspects of string dualities. The lectures mainly focus on these aspects of string dualities. Further lectures regarding supersymmetric gauge theories, quantum gravity and noncommutative field theory are presented. The vast field of research concerning string dualities justifies special attention to their effects on field theory. (author)
Quantum theory and the schism in physics from the postscript to the logic of scientific discovery
Popper, Karl Raimund
1982-01-01
Quantum Theory and the Schism in Physics is one of the three volumes of Karl Popper's Postscript to the Logic of scientific Discovery. The Postscript is the culmination of Popper's work in the philosophy of physics and a new famous attack on subjectivist approaches to philosophy of science.Quantum Theory and the Schism in Physics is the third volume of the Postscript. It may be read independently, but it also forms part of Popper's interconnected argument in the Postscript. It presents Popper's classic statement on quantum physics a
Quantum optics and nuclear clocks: a look at the 2012 physics nobel prize
International Nuclear Information System (INIS)
Herrera-Sancho, Oscar-Andrey
2013-01-01
Pioneering researches in the field of quantum optics are presented. These have laid the foundation for photonics research, that has grasped the particle properties of light to create new technologies and deepen the understanding of the physical laws. The quantum computation and quantum clocks have been highlighted. Individual particles have managed to manipulate without losing its properties in quantum, using photons to immobilize atoms with electric charges (ions) and study their properties. Researches conducted by the French scientist Serge Haroche and American David Wineland nobel prize winners for Physics 2012, have been commented [es
Classical Physics and the Bounds of Quantum Correlations.
Frustaglia, Diego; Baltanás, José P; Velázquez-Ahumada, María C; Fernández-Prieto, Armando; Lujambio, Aintzane; Losada, Vicente; Freire, Manuel J; Cabello, Adán
2016-06-24
A unifying principle explaining the numerical bounds of quantum correlations remains elusive, despite the efforts devoted to identifying it. Here, we show that these bounds are indeed not exclusive to quantum theory: for any abstract correlation scenario with compatible measurements, models based on classical waves produce probability distributions indistinguishable from those of quantum theory and, therefore, share the same bounds. We demonstrate this finding by implementing classical microwaves that propagate along meter-size transmission-line circuits and reproduce the probabilities of three emblematic quantum experiments. Our results show that the "quantum" bounds would also occur in a classical universe without quanta. The implications of this observation are discussed.
ReleQuant – Improving teaching and learning in quantum physics through educational design research
Directory of Open Access Journals (Sweden)
Berit Bungum
2015-05-01
Full Text Available Quantum physics and relativity are demanding for teachers and students, but have the potential for students to experience physics as fascinating and meaningful. Project ReleQuant engaged in educational design research to improve teaching and learning in these topics in Norwegian upper secondary schools. The paper focuses on the first cycle of development of a teaching module on quantum physics and how design principles were developed. We construct the design principles by reviewing relevant research literature and conducting three pilot studies. The process resulted in the following principles for designing the quantum physics teaching module: 1 clarify how quantum physics breaks with classical physics; 2 use simulations of phenomena that cannot be experienced directly; 3 provide students to use written and oral language; 4 address and discuss wave-particle duality and the uncertainty
Michelsen, Eric L
2014-01-01
Quirky Quantum Concepts explains the more important and more difficult concepts in theoretical quantum mechanics, especially those which are consistently neglected or confusing in many common expositions. The emphasis is on physical understanding, which is necessary for the development of new, cutting edge science. In particular, this book explains the basis for many standard quantum methods, which are too often presented without sufficient motivation or interpretation. The book is not a simplification or popularization: it is real science for real scientists. Physics includes math, and this book does not shy away from it, but neither does it hide behind it. Without conceptual understanding, math is gibberish. The discussions here provide the experimental and theoretical reasoning behind some of the great discoveries, so the reader may see how discoveries arise from a rational process of thinking, a process which Quirky Quantum Concepts makes accessible to its readers. Quirky Quantum Concepts is therefore a s...
Quantum Erasure: Quantum Interference Revisited
Walborn, Stephen P.; Cunha, Marcelo O. Terra; Pádua, Sebastião; Monken, Carlos H.
2005-01-01
Recent experiments in quantum optics have shed light on the foundations of quantum physics. Quantum erasers - modified quantum interference experiments - show that quantum entanglement is responsible for the complementarity principle.
Energy Technology Data Exchange (ETDEWEB)
Ecker, Gerhard [Wien Univ. (Austria). Fakultaet fuer Physik
2017-07-01
The following topics are dealt with: Physics around 1900, the way to quantum mechanics, quantum field theory with quantum electrodynamics as prototype, the crisis of quantum field theory, from the beta decay to the electroweak gauge theory, quantum chromodynamics as quantum field theory of the strong nuclear force, the standard model of the fundamental interactions, physics beyond the standard model. (HSI)
Formal and physical equivalence in two cases in contemporary quantum physics
Fraser, Doreen
2017-08-01
The application of analytic continuation in quantum field theory (QFT) is juxtaposed to T-duality and mirror symmetry in string theory. Analytic continuation-a mathematical transformation that takes the time variable t to negative imaginary time-it-was initially used as a mathematical technique for solving perturbative Feynman diagrams, and was subsequently the basis for the Euclidean approaches within mainstream QFT (e.g., Wilsonian renormalization group methods, lattice gauge theories) and the Euclidean field theory program for rigorously constructing non-perturbative models of interacting QFTs. A crucial difference between theories related by duality transformations and those related by analytic continuation is that the former are judged to be physically equivalent while the latter are regarded as physically inequivalent. There are other similarities between the two cases that make comparing and contrasting them a useful exercise for clarifying the type of argument that is needed to support the conclusion that dual theories are physically equivalent. In particular, T-duality and analytic continuation in QFT share the criterion for predictive equivalence that two theories agree on the complete set of expectation values and the mass spectra and the criterion for formal equivalence that there is a "translation manual" between the physically significant algebras of observables and sets of states in the two theories. The analytic continuation case study illustrates how predictive and formal equivalence are compatible with physical inequivalence, but not in the manner of standard underdetermination cases. Arguments for the physical equivalence of dual theories must cite considerations beyond predictive and formal equivalence. The analytic continuation case study is an instance of the strategy of developing a physical theory by extending the formal or mathematical equivalence with another physical theory as far as possible. That this strategy has resulted in
Quantum physics in the nanoworld Schrödinger's cat and the dwarfs
Lüth, Hans
2013-01-01
The book deals with all essential aspects of non-relativistic quantum physics up to the quantization of fields. In contrast to common textbooks of quantum mechanics, modern experiments are described both for the purpose of foundation of the theory and in relation to recent applications. In this respect applications to nano-electronics as well as the realization of quantum-bits are presented and discussed. Furthermore, links are made to other important research fields and applications, such as elementary particle physics, solid state physics and nuclear magnetic resonance tomography in medicine. Even though the representation of the topics is largely performed in terms of Dirac´s bra-ket notation and by use of commutator algebra, the concrete description of the physical basis and the corresponding theoretical concepts are emphasized. Because of little requirement of complex mathematics, the book is suitable as an introduction into quantum physics, not only for physicists but also for chemists, biologists, eng...
Pykacz, Jarosław
2015-01-01
This Brief presents steps towards elaborating a new interpretation of quantum mechanics based on a specific version of Łukasiewicz infinite-valued logic. It begins with a short survey of main interpretations of quantum mechanics already proposed, as well as various models of many-valued logics and previous attempts to apply them for the description of quantum phenomena. The prospective many-valued interpretation of quantum mechanics is soundly based on a theorem concerning the isomorphic representation of Birkhoff-von Neumann quantum logic in the form of a special Łukasiewicz infinite-valued logic endowed with partially defined conjunctions and disjunctions.
Problems and solutions in quantum chemistry and physics
Johnson, Charles S
1988-01-01
Unusually varied problems, with detailed solutions, cover quantum mechanics, wave mechanics, angular momentum, molecular spectroscopy, scattering theory, more. 280 problems, plus 139 supplementary exercises.
Directory of Open Access Journals (Sweden)
Francisco Savall Alemany
2017-01-01
Full Text Available The effectiveness of the problem based teaching on the science learning has been highlighted by the didactic research. This teaching model is characterized by organizing the units around problems and by proposing a research plan to find a solution which requires concepts and models to be introduced in a functional way, as possible solutions to the problem. In this article we present a problem based unit for teaching quantum physics in introductory physics courses and we analyze in detail the teaching strategy that we follow to build a model to explain the emission and absorption of radiation.
Bender, Carl M.; Fring, Andreas; Guenther, Uwe; Jones, Hugh F.
2012-01-01
This is a call for contributions to a special issue of Journal of Physics A: Mathematical and Theoretical dedicated to quantum physics with non-Hermitian operators. The main motivation behind this special issue is to gather together recent results, developments and open problems in this rapidly evolving field of research in a single comprehensive volume. We expect that such a special issue will become a valuable reference for the broad scientific community working in mathematical and theoretical physics. The issue will be open to all contributions containing new results on non-Hermitian theories which are explicitly PT-symmetric and/or pseudo-Hermitian or quasi-Hermitian. The main novelties in the past years in this area have been many experimental observations, realizations, and applications of PT symmetric Hamiltonians in optics and microwave cavities. We especially invite contributions on the theoretical interpretations of these recent PT-symmetric experiments and on theoretical proposals for new experiments. Editorial policy The Guest Editors for this issue are Carl Bender, Andreas Fring, Uwe Guenther and Hugh Jones. The areas and topics for this issue include, but are not limited to: spectral problems novel properties of complex optical potentials PT-symmetry related threshold lasers and spectral singularities construction of metric operators scattering theory supersymmetric theories Lie algebraic and Krein-space methods random matrix models classical and semi-classical models exceptional points in model systems operator theoretic approaches microwave cavities aspects of integrability and exact solvability field theories with indefinite metric All contributions will be refereed and processed according to the usual procedure of the journal. Papers should report original and significant research that has not already been published. Guidelines for preparation of contributions The deadline for contributed papers will be 31 March 2012. This deadline will allow the
Körhasan, Nilüfer Didis
2015-01-01
Quantum theory is one of the most successful theories in physics. Because of its abstract, mathematical, and counter-intuitive nature, many students have problems learning the theory, just as teachers experience difficulty in teaching it. Pedagogical research on quantum theory has mainly focused on cognitive issues. However, affective issues about…
Visualization of the Invisible: The Qubit as Key to Quantum Physics
Dür, Wolfgang; Heusler, Stefan
2014-01-01
Quantum mechanics is one of the pillars of modern physics, however rather difficult to teach at the introductory level due to the conceptual difficulties and the required advanced mathematics. Nevertheless, attempts to identify relevant features of quantum mechanics and to put forward concepts of how to teach it have been proposed. Here we present…
Concept of indistinguishable particles in classical and quantum physics
International Nuclear Information System (INIS)
Bach, A.
1988-01-01
The consequences of the following definition of indistinguishability are analyzed. Indistinguishable classical or quantum particles are identical classical or quantum particles in a state characterized by a probability measure, a statistical operator respectively, which is invariant under any permutation of the particles. According to this definition the particles of classical Maxwell-Boltzmann statistics are indistinguishable
Self-organized quantum rings : Physical characterization and theoretical modeling
Fomin, V.M.; Gladilin, V.N.; Devreese, J.T.; Koenraad, P.M.; Fomin, V.M.
2014-01-01
An adequate modeling of the self-organized quantum rings is possible only on the basis of the modern characterization of those nanostructures.We discuss an atomic-scale analysis of the indium distribution of self-organized InGaAs quantum rings (QRs). The analysis of the shape, size and composition
On the suppression of chaos in quantum and classical physics
International Nuclear Information System (INIS)
Fried, H.M.; Gabellini, Y.
1997-01-01
A brief outline is presented of an example of potential-theory quantum chaos, which is suppressed by the full radiative corrections of quantum field theory. A similar mechanism may be devised and applied to classically chaotic systems, and provides an example in which an explicit diminution of the original chaos becomes apparent. (author)
Quantum physics in the nanoworld. Schroedinger's cat and the dwarfs
Energy Technology Data Exchange (ETDEWEB)
Lueth, Hans [Forschungszentrum Juelich GmbH (Germany). PGI-9 Semiconductor Nanoelectronics and Juelich Aachen Research Alliance (JARA)
2013-07-01
Gives a step-by-step derivation of the physical basis of quantum mechanics without using complex mathematics. Provides a close linking of experiment and theory. Describes most modern experiments related to nanoscience and to the foundation of quantum theory. Provides appendices describing the preparation of nanostructures and the importance of interface physics for nanoscience. Contains more than 40 problems to deepen the understanding. English language version of a successful German textbook. The book deals with all essential aspects of non-relativistic quantum physics up to the quantization of fields. In contrast to common textbooks of quantum mechanics, modern experiments are described both for the purpose of foundation of the theory and in relation to recent applications. In this respect applications to nano-electronics as well as the realization of quantum-bits are presented and discussed. Furthermore, links are made to other important research fields and applications, such as elementary particle physics, solid state physics and nuclear magnetic resonance tomography in medicine. Even though the representation of the topics is largely performed in terms of Dirac's bra-ket notation and by use of commutator algebra, the concrete description of the physical basis and the corresponding theoretical concepts are emphasized. Because of little requirement of complex mathematics, the book is suitable as an introduction into quantum physics, not only for physicists but also for chemists, biologists, engineers, computer scientists and even for philosophers as far as they are interested in natural philosophy and epistomology.
Exponential Sensitivity and its Cost in Quantum Physics.
Gilyén, András; Kiss, Tamás; Jex, Igor
2016-02-10
State selective protocols, like entanglement purification, lead to an essentially non-linear quantum evolution, unusual in naturally occurring quantum processes. Sensitivity to initial states in quantum systems, stemming from such non-linear dynamics, is a promising perspective for applications. Here we demonstrate that chaotic behaviour is a rather generic feature in state selective protocols: exponential sensitivity can exist for all initial states in an experimentally realisable optical scheme. Moreover, any complex rational polynomial map, including the example of the Mandelbrot set, can be directly realised. In state selective protocols, one needs an ensemble of initial states, the size of which decreases with each iteration. We prove that exponential sensitivity to initial states in any quantum system has to be related to downsizing the initial ensemble also exponentially. Our results show that magnifying initial differences of quantum states (a Schrödinger microscope) is possible; however, there is a strict bound on the number of copies needed.
The quantum physics bible the definitive guide to 200 years of subatomic science
Clegg, Brian
2017-01-01
An easy-to-understand guide to the complex subject of quantum physics. Quantum physics is how scientists describe the world of the very small. For other people, however, the rules of quantum physics seem to violate all logic: How can a particle be in more than one place at the same time? How can it tunnel through an impenetrable barrier? How can a cat in a box be both alive and dead? This book explains the complexities of quantum physics in bite-sized "lessons" that make it clear and accessible to all readers. The sections and chapters are: 1. Atoms -- quantum; quantum physics in everyday life; the periodic table; atoms and nuclei; isotopes; hydrogen atom (energy levels and spectra) 2. Photons -- photoelectric effect; thermal emission and the Planck distribution; wave particle duality (Young's slit experiment) 3. Quantum devices -- superconductors; transistor, diode; light-emitting diode; laser 4. Spin -- spin; fermions; exclusion principle; Fermi Dirac distribution; Bose-Einstein statistics 5. Wave Mechan...
Héraud, Jean-Loup; Lautesse, Philippe; Ferlin, Fabrice; Chabot, Hugues
2017-01-01
Our work extends a previous study of epistemological presuppositions in teaching quantum physics in upper scientific secondary school in France. Here, the problematic reference of quantum theory's concepts is treated at the ontological level (the counterintuitive nature of quantum objects). We consider the approach of using narratives describing…
International Nuclear Information System (INIS)
Margaritondo, G
2003-01-01
Quantum physics is the backbone of modern science: therefore, a correct first step is essential for students' success in many different disciplines. Unfortunately, many didactic approaches are still complicated, potentially confusing and often historically wrong. An alternate, simple, stimulating and historically correct approach is outlined here
You err, Einstein.. Newton, Einstein, Heisenberg, and Feynman discuss quantum physics
International Nuclear Information System (INIS)
Fritzsch, Harald
2008-01-01
Harald Fritzsch and his star physicists Einstein, Heisenberg, and Feynman explain the central concept of nowadays physics, quantum mechanics, without it nothing goes in modern world. And the great Isaac newton puts the questions, which all would put
On estimating perturbative coefficients in quantum field theory and statistical physics
International Nuclear Information System (INIS)
Samuel, M.A.; Stanford Univ., CA
1994-05-01
The authors present a method for estimating perturbative coefficients in quantum field theory and Statistical Physics. They are able to obtain reliable error-bars for each estimate. The results, in all cases, are excellent
Cracking quantum physics you, this book and 200 years of sub-atomic science
Clegg, Brian
2017-01-01
Enter the invisible world of sub-atomic physics and discover the very core of existence. Cracking Quantum Physics takes you through every area of particle physics to clearly explain how our world was, and is, created, and breaks down the most complex theories into easily understandable elements. Subjects covered include:-Time travel-The Higgs field-Dark Matter-The anatomy of the elements-Enter the atom-Quantum reality-Quantum tunnelling-Electrodynamics-Accelerators and colliders-The Zeno effectAn easy-to-understand guide to some of the most complex and intriguing topics: Cracking Quantum Physics is a must-read for anyone who has ever wondered about the underlying forces and materials that make up the world as we know it.
A short course in quantum information theory an approach from theoretical physics
Diosi, Lajos
2011-01-01
This short and concise primer takes the vantage point of theoretical physics and the unity of physics. It sets out to strip the burgeoning field of quantum information science to its basics by linking it to universal concepts in physics. An extensive lecture rather than a comprehensive textbook, this volume is based on courses delivered over several years to advanced undergraduate and beginning graduate students, but essentially it addresses anyone with a working knowledge of basic quantum physics. Readers will find these lectures a most adequate entry point for theoretical studies in this field. For the second edition, the authors has succeeded in adding many new topics while sticking to the conciseness of the overall approach. A new chapter on qubit thermodynamics has been added, while new sections and subsections have been incorporated in various chapter to deal with weak and time-continuous measurements, period-finding quantum algorithms and quantum error corrections. From the reviews of the first edition...
Quantum Mechanics at the Crossroads New Perspectives from History, Philosophy and Physics
Evans, James
2007-01-01
Quantum mechanics is a beautiful, strange and successful theory that originated in the 1920s. The theory, which Niels Bohr regarded as finished and complete, has in the last few decades rapidly developed in unexpected directions. An intense new focus on the stranger aspects of the theory, including entanglement and nonlocality, has resulted in new perceptions of the foundations of quantum mechanics, as well as surprising new exploitations of quantum phenomena. Historians and philosophers of science have also renewed their attention to quantum mechanics, opening up its human dimensions and asking searching questions about its meaning. This volume brings together new insights from different vantage points: Historians of physics, such as J. L. Heilbron; philosophers of science, such as Abner Shimony and Michel Bitbol; and quantum physicists, such as Wolfgang Ketterle and Roland Omnès, join forces to tackle essential questions in quantum mechanics and its interpretation. All the authors have written for a broad ...
Nuclear and particle physics applications of the Bohm picture of quantum mechanics
International Nuclear Information System (INIS)
Miranda, A
2009-01-01
Aproximation methods for calculating individual particle/field motions in spacetime at the quantum level of accuracy (a key feature of the Bohm picture (BP) of quantum mechanics) are studied. This sharply illuminates not only the deep quantum structures underlying any observable quantum statistical laws of motion of particles and fields in spacetime, but also how the continuous merging of the so-called classical and quantal modes of description actually occurs, with no breaks anywhere. Modern textbook presentations of Quantum Theory are used throughout, but only to provide the necessary, already existing, tested formalisms and calculational techniques. New coherent insights, reinterpretations of old solutions and results, and new (in principle testable) quantitative and qualitative predictions can be obtained on the basis of the BP that complete the standard type of postdictions and predictions. Most of the dead wood still cluttering discussions on the meaning of Quantum Theory and the role of the BP is by-passed. We shall try to draw attention to the physics of this unfortunately hardly known novel formulation of Quantum Theory by giving additional illustrative examples inspired from the daily practices of contemporary Nuclear and Particle Physics, subjects that as yet have not been thoroughly reinterpreted within the BP. These fields of research offer excellent oppurtunities for explaining and illustrating the significance of time in quantum transitions, as well as the closely related features of quantum non-locality and quantum wholeness, as hard physical facts. We claim that in addition we can obtain a substantial gain in predictive powers of the underlying, all-encompassing, Quantum Theory.
Report and Recommendations on Multimedia Materials for Teaching and Learning Quantum Physics
International Nuclear Information System (INIS)
Mason, B.; Debowska, E.; Arpornthip, T.
2015-01-01
An international collaboration of physicists, affiliated with Multimedia Physics for Teaching and Learning (MPTL) and MERLOT, performed a survey and review of multimedia-based learning materials for quantum physics and quantum mechanics. The review process was based on more than a decade of experience with similar topical learning material reviews. A total of approximately 250 items were considered for review and eight were recommended by the reviewers. These are described in this report. Observations about quantum learning resources and multimedia tools are included.
Measurement and the mathematical apparatus of quantum physics
International Nuclear Information System (INIS)
Slavnov, D.A.
2007-01-01
A scheme for constructing quantum mechanics in which the Hilbert space and linear operators are not primary elements on the theory is described. Some variant of the algebraic approach is instead considered. The elements of a noncommutative algebra (observables) and functionals in this algebra serve as the primary components of the theory. Such a scheme allows one to use the formalism of the classical (Kolmogorovian) theory of probability, and to reproduce the mathematical formalism of standard quantum mechanics and to specify borders of its applicability. A brief review of necessary data from the theory of algebras and probability theory is given. The manner is described in which the considered mathematical scheme agrees with the theory of quantum measurements and allows one to avoid quantum paradoxes [ru
Nobel Prize in physics 1985: Quantum Hall effect
International Nuclear Information System (INIS)
Herrmann, R.
1986-01-01
The conditions (like very strong magnetic fields, ultralow temperatures, and occurrence of a two-dimensional electron gas in microelectronic structures) for the measurement of the quantum Hall effect are explained. Two possible measuring methods are described. Measuring results for p-Si-MOSFET, GaAs/AlGaAs heterojuntions and grain boundaries in InSb crystals are reported. Differences between normal (integer) and fractional quantum Hall effect are discussed. One of the important consequences is that by means of the quantum Hall effect the value h/e 2 can be determined with very high accuracy. In 1985 Klaus von Klitzing was awarded the Nobel Prize for his work on the quantum Hall effect
Probing models of quantum decoherence in particle physics and cosmology
Energy Technology Data Exchange (ETDEWEB)
Mavromatos, Nikolaos E; Sarkar, Sarben [King' s College London, Department of Physics, Theoretical Physics, Strand London WC2R 2LS (United Kingdom)
2007-05-15
In this review we discuss the string theoretical motivations for induced decoherence and deviations from ordinary quantum-mechanical behaviour; this leads to intrinsic CPT violation in the context of an extended class of quantum-gravity models. We proceed to a description of precision tests of CPT symmetry and quantum mechanics using mainly neutral kaons and neutrinos. We emphasize the possibly unique role of neutral meson factories in providing tests of models where the quantum-mechanical CPT operator is not well-defined, leading to modifications of Einstein-Podolsky-Rosen particle correlators. Finally, we discuss experimental probes of decoherence in cosmology, including studies of dissipative relaxation models of dark energy in non-critical (non-equilibrium) string theory and the associated modifications of the Boltzmann equation for the evolution of species abundances.
Quantum physics and philosophy, in dialogue with Shimon Malin
International Nuclear Information System (INIS)
Shimony, A.
2005-01-01
Full text: The philosophical antecedents of the debate concerning the objectivity or subjectivity of the quantum state will be examined: Hume, Kant, Peirce, Mach. Heisenberg's interpretation of the quantum state in terms of a new modality of the real, namely potentiality. Its antecedents and its implications: the propensity interpretation of probability, entanglement, nonlocality. Philosophical treatments of the measurement problem in quantum mechanics: the Copenhagen interpretation, the Everett interpretation, consistent histories interpretation, stochastic and nonlinear modifications of the Schroedinger equation, hidden variables theories, consciousness as a mechanism for reduction of superpositions. Speculations about philosophical implications of quantum mechanics: the status of temporal becoming, the mind-body problem, evolution of natural law. The relation of these implications to the philosophy of Alfred North Whitehead. (author)
A short course in quantum information theory. An approach from theoretical physics
International Nuclear Information System (INIS)
Diosi, L.
2007-01-01
This short and concise primer takes the vantage point of theoretical physics and the unity of physics. It sets out to strip the burgeoning field of quantum information science to its basics by linking it to universal concepts in physics. An extensive lecture rather than a comprehensive textbook, this volume is based on courses delivered over several years to advanced undergraduate and beginning graduate students, but essentially it addresses anyone with a working knowledge of basic quantum physics. Readers will find these lectures a most adequate entry point for theoretical studies in this field. (orig.)
Statistical physics of black holes as quantum-mechanical systems
Giddings, Steven B.
2013-01-01
Some basic features of black-hole statistical mechanics are investigated, assuming that black holes respect the principles of quantum mechanics. Care is needed in defining an entropy S_bh corresponding to the number of microstates of a black hole, given that the black hole interacts with its surroundings. An open question is then the relationship between this entropy and the Bekenstein-Hawking entropy S_BH. For a wide class of models with interactions needed to ensure unitary quantum evolutio...
International Nuclear Information System (INIS)
Weber, Reinhart
2012-01-01
This textbook mediates in three volumes the matter of the first four semester of the bachelor respectively master course. The otherwise generally usual separate presentation of experimental and theoretical physics is canceled in favor of an integrated treatment. The advances are obvious: The studying is enabled to learn to understand knowledge gotten by means of experiments also immediately in a quantitative formulation. The can equally be used as textbook to an integrated course and to separated courses. Because the relevant theoretical concepts are developed without gap a special book of theoretical physics is unnecessary. Numerous exercise problems deepen the understanding and help directly in the preparation for examinations. The illustrations are mostly presented in two colours. Volume III treats atomic and molecular physics. After a semiclassical presentation the quantum-mechanical foundations are developed and in the following chapters applied to atomic systems and processes. An introduction in the foundations and application of the laser. The closure is formed by a chapter about entangled systems.
A short course in quantum information theory. An approach from theoretical physics. 2. ed.
International Nuclear Information System (INIS)
Diosi, Lajos
2011-01-01
This short and concise primer takes the vantage point of theoretical physics and the unity of physics. It sets out to strip the burgeoning field of quantum information science to its basics by linking it to universal concepts in physics. An extensive lecture rather than a comprehensive textbook, this volume is based on courses delivered over several years to advanced undergraduate and beginning graduate students, but essentially it addresses anyone with a working knowledge of basic quantum physics. Readers will find these lectures a most adequate entry point for theoretical studies in this field. For the second edition, the authors has succeeded in adding many new topics while sticking to the conciseness of the overall approach. A new chapter on qubit thermodynamics has been added, while new sections and subsections have been incorporated in various chapter to deal with weak and time-continuous measurements, period-finding quantum algorithms and quantum error corrections. From the reviews of the first edition: ''The best things about this book are its brevity and clarity. In around 100 pages it provides a tutorial introduction to quantum information theory, including problems and solutions.. it's worth a look if you want to quickly get up to speed with the language and central concepts of quantum information theory, including the background classical information theory.'' (Craig Savage, Australian Physics, Vol. 44 (2), 2007). (orig.)
International Nuclear Information System (INIS)
Halim, A.A.; Meerah, T.S.; Lilia Halim
2009-01-01
A study on students' misconceptions on quantum physics is rarely being done, because the target audience is quite small. It is important to understand quantum physics concepts correctly especially for science students. This study was under taken to help students identify their misconceptions at the early stage. The aim of this study is to develop a diagnostic test which can access the students' misconceptions, and use the findings for the benefits of quantum physics courses. A multiple-choice Quantum Physics Diagnostic Test (QPDT), that involves concepts of light, atomic model, particle-wave dualism, wave function, and potential energy, was administered to 200 university students. The results shows that many students use the classical concepts to describe the quantum phenomenon. For example students describe light only as a wave, an electron only as a particle, and that the atomic structure is parallel to the solar system. To overcome these problems, it is suggested that lecturers spend more time in explaining the basic definitions and using analogies in quantum physics teaching. (author)
From classical to quantum mechanics: ``How to translate physical ideas into mathematical language''
Bergeron, H.
2001-09-01
Following previous works by E. Prugovečki [Physica A 91A, 202 (1978) and Stochastic Quantum Mechanics and Quantum Space-time (Reidel, Dordrecht, 1986)] on common features of classical and quantum mechanics, we develop a unified mathematical framework for classical and quantum mechanics (based on L2-spaces over classical phase space), in order to investigate to what extent quantum mechanics can be obtained as a simple modification of classical mechanics (on both logical and analytical levels). To obtain this unified framework, we split quantum theory in two parts: (i) general quantum axiomatics (a system is described by a state in a Hilbert space, observables are self-adjoints operators, and so on) and (ii) quantum mechanics proper that specifies the Hilbert space as L2(Rn); the Heisenberg rule [pi,qj]=-iℏδij with p=-iℏ∇, the free Hamiltonian H=-ℏ2Δ/2m and so on. We show that general quantum axiomatics (up to a supplementary "axiom of classicity") can be used as a nonstandard mathematical ground to formulate physical ideas and equations of ordinary classical statistical mechanics. So, the question of a "true quantization" with "ℏ" must be seen as an independent physical problem not directly related with quantum formalism. At this stage, we show that this nonstandard formulation of classical mechanics exhibits a new kind of operation that has no classical counterpart: this operation is related to the "quantization process," and we show why quantization physically depends on group theory (the Galilei group). This analytical procedure of quantization replaces the "correspondence principle" (or canonical quantization) and allows us to map classical mechanics into quantum mechanics, giving all operators of quantum dynamics and the Schrödinger equation. The great advantage of this point of view is that quantization is based on concrete physical arguments and not derived from some "pure algebraic rule" (we exhibit also some limit of the correspondence
Experimental quantum simulations of many-body physics with trapped ions.
Schneider, Ch; Porras, Diego; Schaetz, Tobias
2012-02-01
Direct experimental access to some of the most intriguing quantum phenomena is not granted due to the lack of precise control of the relevant parameters in their naturally intricate environment. Their simulation on conventional computers is impossible, since quantum behaviour arising with superposition states or entanglement is not efficiently translatable into the classical language. However, one could gain deeper insight into complex quantum dynamics by experimentally simulating the quantum behaviour of interest in another quantum system, where the relevant parameters and interactions can be controlled and robust effects detected sufficiently well. Systems of trapped ions provide unique control of both the internal (electronic) and external (motional) degrees of freedom. The mutual Coulomb interaction between the ions allows for large interaction strengths at comparatively large mutual ion distances enabling individual control and readout. Systems of trapped ions therefore exhibit a prominent system in several physical disciplines, for example, quantum information processing or metrology. Here, we will give an overview of different trapping techniques of ions as well as implementations for coherent manipulation of their quantum states and discuss the related theoretical basics. We then report on the experimental and theoretical progress in simulating quantum many-body physics with trapped ions and present current approaches for scaling up to more ions and more-dimensional systems.
Fundamentals of quantum physics. Textbook for students of science and engineering
Energy Technology Data Exchange (ETDEWEB)
Pereyra Padilla, Pedro [Universidad Autonoma Metropolitana, Mexico City (Mexico). Fisica Teorica y Materia Condensada
2012-07-01
A clearly written basic textbook with a good balance between basic explanations and applications. Supplies new views on eigenvalues and eigenfunctions in quantum mechanics. Gives background needed to understand quantum cryptography, teleportation and computation. Provides a clear and consistent understanding of quantum concepts and quantum phenomenology. This book presents a comprehensive course of quantum mechanics for undergraduate and graduate students. After a brief outline of the innovative ideas that lead up to the quantum theory, the book reviews properties of the Schroedinger equation, the quantization phenomena and the physical meaning of wave functions. The book discusses, in a direct and intelligible style, topics of the standard quantum formalism like the dynamical operators and their expected values, the Heisenberg and matrix representation, the approximate methods, the Dirac notation, harmonic oscillator, angular momentum and hydrogen atom, the spin-field and spin-orbit interactions, identical particles and Bose-Einstein condensation etc. Special emphasis is devoted to study the tunneling phenomena, transmission coefficients, phase coherence, energy levels splitting and related phenomena, of interest for quantum devices and heterostructures. The discussion of these problems and the WKB approximation is done using the transfer matrix method, introduced at a tutorial level. This book is a textbook for upper undergraduate physics and electronic engineering students.
Fundamentals of quantum physics. Textbook for students of science and engineering
International Nuclear Information System (INIS)
Pereyra Padilla, Pedro
2012-01-01
A clearly written basic textbook with a good balance between basic explanations and applications. Supplies new views on eigenvalues and eigenfunctions in quantum mechanics. Gives background needed to understand quantum cryptography, teleportation and computation. Provides a clear and consistent understanding of quantum concepts and quantum phenomenology. This book presents a comprehensive course of quantum mechanics for undergraduate and graduate students. After a brief outline of the innovative ideas that lead up to the quantum theory, the book reviews properties of the Schroedinger equation, the quantization phenomena and the physical meaning of wave functions. The book discusses, in a direct and intelligible style, topics of the standard quantum formalism like the dynamical operators and their expected values, the Heisenberg and matrix representation, the approximate methods, the Dirac notation, harmonic oscillator, angular momentum and hydrogen atom, the spin-field and spin-orbit interactions, identical particles and Bose-Einstein condensation etc. Special emphasis is devoted to study the tunneling phenomena, transmission coefficients, phase coherence, energy levels splitting and related phenomena, of interest for quantum devices and heterostructures. The discussion of these problems and the WKB approximation is done using the transfer matrix method, introduced at a tutorial level. This book is a textbook for upper undergraduate physics and electronic engineering students.
"Shut up and calculate": the available discursive positions in quantum physics courses
Johansson, Anders; Andersson, Staffan; Salminen-Karlsson, Minna; Elmgren, Maja
2018-03-01
Educating new generations of physicists is often seen as a matter of attracting good students, teaching them physics and making sure that they stay at the university. Sometimes, questions are also raised about what could be done to increase diversity in recruitment. Using a discursive perspective, in this study of three introductory quantum physics courses at two Swedish universities, we instead ask what it means to become a physicist, and whether certain ways of becoming a physicist and doing physics is privileged in this process. Asking the question of what discursive positions are made accessible to students, we use observations of lectures and problem solving sessions together with interviews with students to characterize the discourse in the courses. Many students seem to have high expectations for the quantum physics course and generally express that they appreciate the course more than other courses. Nevertheless, our analysis shows that the ways of being a "good quantum physics student" are limited by the dominating focus on calculating quantum physics in the courses. We argue that this could have negative consequences both for the education of future physicists and the discipline of physics itself, in that it may reproduce an instrumental "shut up and calculate"-culture of physics, as well as an elitist physics education. Additionally, many students who take the courses are not future physicists, and the limitation of discursive positions may also affect these students significantly.
The scientifiv way of thinking in statistics, statistical physics and quantum mechanics
Săvoiu, Gheorghe
2008-01-01
This paper focuses on the way of thinking in both classical and modern Physics and Statistics, Statistical Mechanics or Statistical Physics and Quantum Mechanics. These different statistical ways of thinking and their specific methods have generated new fields for new activities and new scientific disciplines, like Econophysics (between Economics and Physics), Sociophysics (between Sociology and Physics), Mediaphysics (between all media and comunication sciences), etc. After describing some r...
The scientific way of thinking in statistics, statistical physics and quantum mechanics
Săvoiu, Gheorghe
2008-01-01
This paper focuses on the way of thinking in both classical and modern Physics and Statistics, Statistical Mechanics or Statistical Physics and Quantum Mechanics. These different statistical ways of thinking and their specific methods have generated new fields for new activities and new scientific disciplines, like Econophysics (between Economics and Physics), Sociophysics (between Sociology and Physics), Mediaphysics (between all media and comunication sciences), etc. After describing some r...
Bohmian mechanics. The physics and mathematics of quantum theory
International Nuclear Information System (INIS)
Duerr, Detlef; Teufel, Stefan
2009-01-01
Bohmian Mechanics was formulated in 1952 by David Bohm as a complete theory of quantum phenomena based on a particle picture. It was promoted some decades later by John S. Bell, who, intrigued by the manifestly nonlocal structure of the theory, was led to his famous Bell's inequalities. Experimental tests of the inequalities verified that nature is indeed nonlocal. Bohmian mechanics has since then prospered as the straightforward completion of quantum mechanics. This book provides a systematic introduction to Bohmian mechanics and to the mathematical abstractions of quantum mechanics, which range from the self-adjointness of the Schroedinger operator to scattering theory. It explains how the quantum formalism emerges when Boltzmann's ideas about statistical mechanics are applied to Bohmian mechanics. The book is self-contained, mathematically rigorous and an ideal starting point for a fundamental approach to quantum mechanics. It will appeal to students and newcomers to the field, as well as to established scientists seeking a clear exposition of the theory. (orig.)
Bohmian mechanics. The physics and mathematics of quantum theory
Energy Technology Data Exchange (ETDEWEB)
Duerr, Detlef [Muenchen Univ. (Germany). Fakultaet Mathematik; Teufel, Stefan [Tuebingen Univ. (Germany). Mathematisches Inst.
2009-07-01
Bohmian Mechanics was formulated in 1952 by David Bohm as a complete theory of quantum phenomena based on a particle picture. It was promoted some decades later by John S. Bell, who, intrigued by the manifestly nonlocal structure of the theory, was led to his famous Bell's inequalities. Experimental tests of the inequalities verified that nature is indeed nonlocal. Bohmian mechanics has since then prospered as the straightforward completion of quantum mechanics. This book provides a systematic introduction to Bohmian mechanics and to the mathematical abstractions of quantum mechanics, which range from the self-adjointness of the Schroedinger operator to scattering theory. It explains how the quantum formalism emerges when Boltzmann's ideas about statistical mechanics are applied to Bohmian mechanics. The book is self-contained, mathematically rigorous and an ideal starting point for a fundamental approach to quantum mechanics. It will appeal to students and newcomers to the field, as well as to established scientists seeking a clear exposition of the theory. (orig.)
Ensembles and Experiments in Classical and Quantum Physics
Neumaier, Arnold
A philosophically consistent axiomatic approach to classical and quantum mechanics is given. The approach realizes a strong formal implementation of Bohr's correspondence principle. In all instances, classical and quantum concepts are fully parallel: the same general theory has a classical realization and a quantum realization. Extending the ''probability via expectation'' approach of Whittle to noncommuting quantities, this paper defines quantities, ensembles, and experiments as mathematical concepts and shows how to model complementarity, uncertainty, probability, nonlocality and dynamics in these terms. The approach carries no connotation of unlimited repeatability; hence it can be applied to unique systems such as the universe. Consistent experiments provide an elegant solution to the reality problem, confirming the insistence of the orthodox Copenhagen interpretation on that there is nothing but ensembles, while avoiding its elusive reality picture. The weak law of large numbers explains the emergence of classical properties for macroscopic systems.
Introduction to modern theoretical physics. Volume II. Quantum theory and statistical physics
International Nuclear Information System (INIS)
Harris, E.G.
1975-01-01
The topics discussed include the history and principles, some solvable problems, and symmetry in quantum mechanics, interference phenomena, approximation methods, some applications of nonrelativistic quantum mechanics, relativistic wave equations, quantum theory of radiation, second quantization, elementary particles and their interactions, thermodynamics, equilibrium statistical mechanics and its applications, the kinetic theory of gases, and collective phenomena
On the existence of pointlike localized fields in conformally invariant quantum physics
International Nuclear Information System (INIS)
Joerss, M.
1992-11-01
In quantum field theory the existence of pointlike localizable objects called 'fields' is a preassumption. Since charged fields are in general not observable this situation is unsatisfying from a quantum physics point of view. Indeed in any quantum theory the existence of fields should follow from deeper physical concepts and more natural first principles like stability, locality, causality and symmetry. In the framework of algebraic quantum field theory with Haag-Kastler nets of local observables this is presented for the case of conformal symmetry in 1+1 dimensions. Conformal fields are explicitly constructed as limits of observables localized in finite regions of space-time. These fields then allow to derive a geometric identification of modular operators, Haag duality in the vacuum sector, the PCT-theorem and an equivalence theorem for fields and algebras. (orig.)
Physics colloquium: Electron counting in quantum dots in and out of equilibrium
Geneva University
2011-01-01
GENEVA UNIVERSITY Ecole de physique Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 Genève 4 Tél.: (022) 379 62 73 Fax: (022) 379 69 92olé Lundi 31 octobre 2011 17h00 - Ecole de Physique, Auditoire Stueckelberg PHYSICS COLLOQUIUM « Electron counting in quantum dots in and out of equilibrium » Prof. Klaus Ensslin Solid State Physics Laboratory, ETH Zurich, 8093 Zurich, Switzerland Electron transport through quantum dots is governed by Coulomb blockade. Using a nearby quantum point contact the time-dependent charge flow through quantum dots can be monitored on the basis of single electrons. This way electron transport has been investigated in equilibrium as well as out of equilibrium. Recently it has become possible to experimentally verify the fluctuation theorem. The talk will also address electron counting experiments in grapheme. Une verrée ...
Energy Technology Data Exchange (ETDEWEB)
Grawert, G.
1985-01-01
The aim of the textbook now present in fourth edition is the representation of the fundamental physical concepts of the theory of quantum mechanics. It is confined to the nonrelativistic quantum mechanics; however also themes are treated which are in an extended form important just for quantum field theory up to the modern development. (orig./HSI). With 22 figs.
Energy Technology Data Exchange (ETDEWEB)
Grawert, G. (Marburg Univ. (Germany, F.R.). Fachbereich 13 - Physik)
1989-01-01
The aim of the textbook now present in fifth edition is the representation of the fundamental physical concepts of the theory of quantum mechanics. It is confined to the nonrelativistic quantum mechanics; however also themes are treated which are in an extended form important just for quantum field theory up to the modern development. (orig.) With 22 figs.
Quantum Chromodynamics and Nuclear Physics at Extreme Energy Density
Energy Technology Data Exchange (ETDEWEB)
Mueller, B.; Bass, S.A.; Chandrasekharan, S.; Mehen, T.; Springer, R.P.
2005-11-07
The report describes research in theoretical quantum chromodynamics, including effective field theories of hadronic interactions, properties of strongly interacting matter at extreme energy density, phenomenology of relativistic heavy ion collisions, and algorithms and numerical simulations of lattice gauge theory and other many-body systems.
Does Quantum Physics Refute Realism, Materialism and Determinism?
Bunge, Mario
2012-01-01
It is argued that the correct answer to the three questions in the title is "no": that the theses being denied derive from traditional philosophy, not from the way the quantum theories are used. For example, the calculation of the energy spectrum of an atom assumes the autonomous existence of the atom, rather than its dependence upon the observer.…
Quantum chromodynamics effects in electroweak and Higgs physics
Indian Academy of Sciences (India)
Several examples of the often intricate effects of higher-order quantum chromodynamics (QCD) corrections on predictions for hadron-collider observables, are discussed, using the production of electroweak gauge boson and the Standard Model Higgs boson as examples. Particular attention is given to the interplay of QCD ...
Quantum Chromodynamics and Nuclear Physics at Extreme Energy Density
International Nuclear Information System (INIS)
Mueller, B.; Bass, S.A.; Chandrasekharan, S.; Mehen, T.; Springer, R.P.
2005-01-01
The report describes research in theoretical quantum chromodynamics, including effective field theories of hadronic interactions, properties of strongly interacting matter at extreme energy density, phenomenology of relativistic heavy ion collisions, and algorithms and numerical simulations of lattice gauge theory and other many-body systems.
Intermode traces - fundamental interference phenomenon in quantum and wave physics
Kaplan, A.E.; Stifter, P.; Leeuwen, van K.A.H.; Lamb, W.E.; Schleich, W.P.
1998-01-01
Highly regular spatio-temporal or multi-dimensional patterns in the quantum mechanical probability or classical field intensity distributions can appear due to pair interference between individual eigen-modes of the system forming the so called intermode traces. These patterns are strongly
Functional Basis for Efficient Physical Layer Classical Control in Quantum Processors
Ball, Harrison; Nguyen, Trung; Leong, Philip H. W.; Biercuk, Michael J.
2016-12-01
The rapid progress seen in the development of quantum-coherent devices for information processing has motivated serious consideration of quantum computer architecture and organization. One topic which remains open for investigation and optimization relates to the design of the classical-quantum interface, where control operations on individual qubits are applied according to higher-level algorithms; accommodating competing demands on performance and scalability remains a major outstanding challenge. In this work, we present a resource-efficient, scalable framework for the implementation of embedded physical layer classical controllers for quantum-information systems. Design drivers and key functionalities are introduced, leading to the selection of Walsh functions as an effective functional basis for both programing and controller hardware implementation. This approach leverages the simplicity of real-time Walsh-function generation in classical digital hardware, and the fact that a wide variety of physical layer controls, such as dynamic error suppression, are known to fall within the Walsh family. We experimentally implement a real-time field-programmable-gate-array-based Walsh controller producing Walsh timing signals and Walsh-synthesized analog waveforms appropriate for critical tasks in error-resistant quantum control and noise characterization. These demonstrations represent the first step towards a unified framework for the realization of physical layer controls compatible with large-scale quantum-information processing.
One-dimensional chain of quantum molecule motors as a mathematical physics model for muscle fibers
International Nuclear Information System (INIS)
Si Tie-Yan
2015-01-01
A quantum chain model of multiple molecule motors is proposed as a mathematical physics theory for the microscopic modeling of classical force-velocity relation and tension transients in muscle fibers. The proposed model was a quantum many-particle Hamiltonian to predict the force-velocity relation for the slow release of muscle fibers, which has not yet been empirically defined and was much more complicated than the hyperbolic relationships. Using the same Hamiltonian model, a mathematical force-velocity relationship was proposed to explain the tension observed when the muscle was stimulated with an alternative electric current. The discrepancy between input electric frequency and the muscle oscillation frequency could be explained physically by the Doppler effect in this quantum chain model. Further more, quantum physics phenomena were applied to explore the tension time course of cardiac muscle and insect flight muscle. Most of the experimental tension transient curves were found to correspond to the theoretical output of quantum two- and three-level models. Mathematical modeling electric stimulus as photons exciting a quantum three-level particle reproduced most of the tension transient curves of water bug Lethocerus maximus. (special topic)
A unified approach to classical and quantum physics
International Nuclear Information System (INIS)
Wignall, J.W.G.
1991-01-01
A non-mathematical account of a theory in which particles are pictured not as points but as spatially extended periodic disturbances in a classical background field - objects which vary in form and size according to the interactions they encounter and which, in particular, abruptly collapse to much smaller disturbances when they are detected. This quasi-classical theory treats the classical and quantum domains on the same fundamental footing. It is shown that, when the particle sizes are small compared with their separations, they must satisfy classical laws such as Newton's equations of motion and Maxwell's electrodynamics, but when a particle is close to, or overlaps, the source of interaction its time evolution is given by quantum formulae such as the Schroedinger equation
Molecular physics and chemistry applications of quantum Monte Carlo
International Nuclear Information System (INIS)
Reynolds, P.J.; Barnett, R.N.; Hammond, B.L.; Lester, W.A. Jr.
1985-09-01
We discuss recent work with the diffusion quantum Monte Carlo (QMC) method in its application to molecular systems. The formal correspondence of the imaginary time Schroedinger equation to a diffusion equation allows one to calculate quantum mechanical expectation values as Monte Carlo averages over an ensemble of random walks. We report work on atomic and molecular total energies, as well as properties including electron affinities, binding energies, reaction barriers, and moments of the electronic charge distribution. A brief discussion is given on how standard QMC must be modified for calculating properties. Calculated energies and properties are presented for a number of molecular systems, including He, F, F - , H 2 , N, and N 2 . Recent progress in extending the basic QMC approach to the calculation of ''analytic'' (as opposed to finite-difference) derivatives of the energy is presented, together with an H 2 potential-energy curve obtained using analytic derivatives. 39 refs., 1 fig., 2 tabs
Introduction to quantum chromodynamics (QCD) and the physics of jets
International Nuclear Information System (INIS)
Billoire, Alain; Napoly, Olivier.
1980-12-01
These lecture notes constitute an introduction to Quantum Chromodynamics (QCD), theory of strong interactions. After an elementary presentation of the essential theoretical tools (Lagrangian, renormalization group) and of their consequences for QCD (asymptotic freedom, scaling invariance), we use these to study jets in e + e - annihilation. We thus deal with the problem of infrared divergences and, finally, with the one of the indirect experimental detection of the gluon [fr
We experience more than we comprehend. Quantum physics and quaesions of life
International Nuclear Information System (INIS)
Duerr, H.P.; Oesterreicher, M.
2007-01-01
The quantum physics has been arrived by thinking and experimenting to revolutioning knowledges, which determine our world, also if only few have understood these theories in their real sense. The present book follows the question, whether and how far a consciousness trained by quantum physics can reach more directly to the understanding of questions of life and religious questions than a thinking, which is obliged to classical physics. It deals especially with fundamental existential questions: The theme of personal responsibility, the value of the indivdual existence, the evaluation of the personal I-you relation. Hans Peter Duerr, a personality with guiding qualities, as they are necessary in the new milennium, is the ideal speech partner for the deimension of this theme. The connections of natural sciences and religion, ecology, and sociological change have always driven the Heisenberg successo. How can we speech about that, which science cannot comprehend?. What means self, identity, responsibilit for the quantum physicist? An exciting meeting
We experience more than we comprehend. Quantum physics and questions of life. rev. new ed.
International Nuclear Information System (INIS)
Duerr, Hans-Peter; Oesterreicher-Mollwo, Marianne
2015-01-01
The quantum physics has been arrived by thinking and experimenting to revolutioning knowledges, which determine our world, also if only few have understood these theories in their real sense. The present book follows the question, whether and how far a consciousness trained by quantum physics can reach more directly to the understanding of questions of life and religious questions than a thinking, which is obliged to classical physics. It deals especially with fundamental existential questions: The theme of personal responsibility, the value of the individual existence, the evaluation of the personal I-you relation. Hans Peter Duerr, a personality with guiding qualities, as they are necessary in the new millennium, is the ideal speech partner for the dimension of this theme. The connections of natural sciences and religion, ecology, and sociological change have always driven the Heisenberg successor. How can we speech about that, which science cannot comprehend?. What means self, identity, responsibility for the quantum physicist? An exciting meeting.
From a quantum to a classical description of intense laser-atom physics with Bohmian trajectories
International Nuclear Information System (INIS)
Lai, X Y; Cai Qingyu; Zhan, M S
2009-01-01
In this paper, Bohmian mechanics is applied to intense laser-atom physics. The motion of an atomic electron in an intense laser field is obtained from the Bohm-Newton equation. We find that the quantum potential that dominates the quantum effect of a physical system becomes negligible as the electron is driven far from the parent ion by the intense laser field, i.e. the behavior of the electron smoothly tends towards classical soon after the electron is ionized. Our numerical calculations present direct positive evidence for semiclassical trajectory methods in intense laser-atom physics where the motion of the ionized electron is treated by classical mechanics, while quantum mechanics is needed before the ionization.
Quantum Physics Principles and Communication in the Acute Healthcare Setting: A Pilot Study.
Helgeson, Heidi L; Peyerl, Colleen Kraft; Solheim-Witt, Marit
This pilot study explores whether clinician awareness of quantum physics principles could facilitate open communication between patients and providers. In the spirit of action research, this study was conceptualized with a holistic view of human health, using a mixed method design of grounded theory as an emergent method. Instrumentation includes surveys and a focus group discussion with twelve registered nurses working in an acute care hospital setting. Findings document that the preliminary core phenomenon, energy as information, influences communication in the healthcare environment. Key emergent themes include awareness, language, validation, open communication, strategies, coherence, incoherence and power. Research participants indicate that quantum physics principles provide a language and conceptual framework for improving their awareness of communication and interactions in the healthcare environment. Implications of this pilot study support the feasibility of future research and education on awareness of quantum physics principles in other clinical settings. Copyright Â© 2016 Elsevier Inc. All rights reserved.
Visualization of the Invisible: The Qubit as Key to Quantum Physics
Dür, Wolfgang; Heusler, Stefan
2014-11-01
Quantum mechanics is one of the pillars of modern physics, however rather difficult to teach at the introductory level due to the conceptual difficulties and the required advanced mathematics. Nevertheless, attempts to identify relevant features of quantum mechanics and to put forward concepts of how to teach it have been proposed.1-8 Here we present an approach to quantum physics based on the simplest quantum mechanical system—the quantum bit (qubit).1 Like its classical counterpart—the bit—a qubit corresponds to a two-level system, i.e., some system with a physical property that can admit two possible values. While typically a physical system has more than just one property or the property can admit more than just two values, in many situations most degrees of freedom can be considered to be fixed or frozen. Hence a variety of systems can be effectively described as a qubit. For instance, one may consider the spin of an electron or atom, with spin up and spin down as two possible values, and where other properties of the particle such as its mass or its position are fixed. Further examples include the polarization degree of freedom of a photon (horizontal and vertical polarization), two electronic degrees of freedom (i.e., two energy levels) of an atom, or the position of an atom in a double well potential (atom in left or right well). In all cases, only two states are relevant to describe the system.
Nomura, Yasunori; Terning, John; Nekoogar, Farzad
2018-01-01
"Modern physics is rife with provocative and fascinating ideas, from quantum mechanics to the multiverse. But as interesting as these concepts are, they are also easy to understand. This book, written with deft hands by true experts in the field, helps to illuminate some of the most important and game-changing ideas in physics today." Sean M. Carroll "The Multiversal book series is equally unique, providing book-length extensions of the lectures with enough additional depth for those who truly want to explore these fields, while also providing the kind of clarity that is appropriate for interested lay people to grasp the general principles involved. " Lawrence M. Krauss Th...
Quantum non-locality and relativity metaphysical intimations of modern physics
Maudlin, Tim
2011-01-01
The third edition of Quantum Non-Locality and Relativity has been carefully updated to reflect significant developments, including a new chapter covering important recent work in the foundations of physics. A new edition of the premier philosophical study of Bell's Theorem and its implication for the relativistic account of space and timeDiscusses Roderich Tumiulka's explicit, relativistic theory that can reproduce the quantum mechanical violation of Bell's inequality. Discusses the "Free Will Theorem" of John Conway and Simon KochenIntroduces philosophers to the relevant physics and demonstra
Basic course theoretical physics. Vol. 5/1. Quantum mechanics - foundations. 7. upd. ed.
International Nuclear Information System (INIS)
Nolting, Wolfgang
2009-01-01
The favoured basic course theoretical physics covers in seven volumes all fields relevant for the diploma. Each volume mediates well thought the in each semester necessary theoretically-physical tools. Numerous exercise problem with extensive solutions serve for the deepening of the matter. The first part of the fifth volume begins with an inductive foundation of quantum mechanics in order to illustrate after a study and summary of the formal foundations of quantum mechanics on simple model systems the concepts and term formations. The present new edition was fundamentally worked out and supplemented. The meanwhile proved two-color presentation allows a very understandable and fast approach to the matter [de
Some Aspects of Mathematical and Physical Approaches for Topological Quantum Computation
Directory of Open Access Journals (Sweden)
V. Kantser
2011-10-01
Full Text Available A paradigm to build a quantum computer, based on topological invariants is highlighted. The identities in the ensemble of knots, links and braids originally discovered in relation to topological quantum field theory are shown: how they define Artin braid group -- the mathematical basis of topological quantum computation (TQC. Vector spaces of TQC correspond to associated strings of particle interactions, and TQC operates its calculations on braided strings of special physical quasiparticles -- anyons -- with non-Abelian statistics. The physical platform of TQC is to use the topological quantum numbers of such small groups of anyons as qubits and to perform operations on these qubits by exchanging the anyons, both within the groups that form the qubits and, for multi-qubit gates, between groups. By braiding two or more anyons, they acquire up a topological phase or Berry phase similar to that found in the Aharonov-Bohm effect. Topological matter such as fractional quantum Hall systems and novel discovered topological insulators open the way to form system of anyons -- Majorana fermions -- with the unique property of encoding and processing quantum information in a naturally fault-tolerant way. In the topological insulators, due to its fundamental attribute of topological surface state occurrence of the bound, Majorana fermions are generated at its heterocontact with superconductors. One of the key operations of TQC -- braiding of non-Abelian anyons: it is illustrated how it can be implemented in one-dimensional topological isolator wire networks.
Quantum mechanics at the crossroads. New perspectives from history, philosophy and physics
International Nuclear Information System (INIS)
Evans, J.; Thorndike, A.S.
2007-01-01
Quantum mechanics is a beautiful, strange and successful theory that originated in the 1920s. The theory, which Niels Bohr regarded as finished and complete, has in the last few decades rapidly developed in unexpected directions. An intense new focus on the stranger aspects of the theory, including entanglement and nonlocality, has resulted in new perceptions of the foundations of quantum mechanics, as well as surprising new exploitations of quantum phenomena. Historians and philosophers of science have also renewed their attention to quantum mechanics, opening up its human dimensions and asking searching questions about its meaning. This volume brings together new insights from different vantage points: Historians of physics, such as J. L. Heilbron; philosophers of science, such as Abner Shimony and Michel Bitbol; and quantum physicists, such as Wolfgang Ketterle and Roland Omncs, join forces to tackle essential questions in quantum mechanics and its interpretation. All the authors have written for a broad readership, and the resulting volume will appeal to everyone wishing to keep abreast of new developments in quantum mechanics, as well as its history and philosophy. (orig.)
Baily, Charles Raymond
2011-01-01
A common learning goal for modern physics instructors is for students to recognize a difference between the experimental uncertainty of classical physics and the fundamental uncertainty of quantum mechanics. Our studies suggest this notoriously difficult task may be frustrated by the intuitively "realist" perspectives of introductory…
Transport Studies of Quantum Magnetism: Physics and Methods
Energy Technology Data Exchange (ETDEWEB)
Lee, Minhyea [Univ. of Colorado, Boulder, CO (United States)
2017-03-30
The main goal of this project was to understand novel ground states of spin systems probed by thermal and electrical transport measurements. They are well-suited to characterize the nature of low-energy excitations as unique property of the ground state. More specifically, it was aimed to study the transverse electrical conductivity in the presence of non-collinear and non-coplanar spin ordering and the effects of gauge field as well as novel spin excitations as a coherent heat transport channel in insulating quantum magnets. Most of works done during the grant period focused on these topics. As a natural extension of the project's initial goals, the scope was broadened to include transport studies on the spin systems with strong spin-orbit coupling. One particular focus was an exploration of systems with strong magnetic anisotropy combined with non-trivial spin configuration. Magnetic anisotropy is directly related to implement the non-collinear spin ordering to the existing common geometry of planar devices and thus poses a significant potential. Work in this direction includes the comparison of the topological Hall signal under hydrostatic pressure and chemical doping, as well as the angular dependence dependence of the non-collinear spin ordered phase and their evolution up on temperature and field strength. Another focus was centered around the experimental identification of spin-originated heat carrying excitation in quasi two dimensional honeycomb lattice, where Kitaev type of quantum spin liquid phase is expected to emerge. In fact, when its long range magnetic order is destroyed by the applied field, we discovered anomalously large enhancement of thermal conductivity, for which proximate Kitaev excitations in field-induced spin liquid state are responsible for. This work, combined with further investigations in materials in the similar class may help establish the experimental characterization of new quantum spin liquid and their unique low energy
International Workshop on "Intersubband Transitions in Quantum Wells : Physics and Applications"
Su, Yan-Kuin
1998-01-01
The International Workshop on "Intersubband Transitions in Quantum Wells:: Physics and Applications," was held at National Cheng Kung University, in Tainan, Taiwan, December 15-18, 1997. The objective of the Workshop is to facilitate the presentation and discussion of the recent results in theoretical, experimental, and applied aspects of intersubband transitions in quantum wells and dots. The program followed the tradition initiated at the 1991 conference in Cargese-France, the 1993 conference in Whistler, B. C. Canada, and the 1995 conference in Kibbutz Ginosar, Israel. Intersubband transitions in quantum wells and quantum dots have attracted considerable attention in recent years, mainly due to the promise of various applications in the mid- and far-infrared regions (2-30 J. lm). Over 40 invited and contributed papers were presented in this four-day workshop, with topics covered most aspects of the intersubband transition phenomena including: the basic intersubband transition processes, multiquantum well i...
Ligare, Martin
2016-05-01
Multiple-pulse NMR experiments are a powerful tool for the investigation of molecules with coupled nuclear spins. The product operator formalism provides a way to understand the quantum evolution of an ensemble of weakly coupled spins in such experiments using some of the more intuitive concepts of classical physics and semi-classical vector representations. In this paper I present a new way in which to interpret the quantum evolution of an ensemble of spins. I recast the quantum problem in terms of mixtures of pure states of two spins whose expectation values evolve identically to those of classical moments. Pictorial representations of these classically evolving states provide a way to calculate the time evolution of ensembles of weakly coupled spins without the full machinery of quantum mechanics, offering insight to anyone who understands precession of magnetic moments in magnetic fields.
Fundamentals of Quantum Physics Textbook for Students of Science and Engineering
Pereyra, Pedro
2012-01-01
This book presents a comprehensive course of quantum mechanics for undergraduate and graduate students. After a brief outline of the innovative ideas that lead up to the quantum theory, the book reviews properties of the Schrödinger equation, the quantization phenomena and the physical meaning of wave functions. The book discusses, in a direct and intelligible style, topics of the standard quantum formalism like the dynamical operators and their expected values, the Heisenberg and matrix representation, the approximate methods, the Dirac notation, harmonic oscillator, angular momentum and hydrogen atom, the spin-field and spin-orbit interactions, identical particles and Bose-Einstein condensation etc. Special emphasis is devoted to study the tunneling phenomena, transmission coefficients, phase coherence, energy levels splitting and related phenomena, of interest for quantum devices and heterostructures. The discussion of these problems and the WKB approximation is done using the transfer matrix method, intr...
The mean field in many body quantum physics
International Nuclear Information System (INIS)
Llano, M. de
1984-01-01
As an introduction to the quantum problem of many bodies we present a panoramic view of the most elementary theories called mean field theories. They comprise: i) the fermions ideal gas theory which implies, in a simple manner, the stability of white dwarf stars and of neutron stars, ii) the Hartree-Fock approximation for thermodynamical systems which is presented here in the context of a liquid-crystal phase transition, and iii) the Thomas-Fermi theory which is applied to the total binding energy of neutral atoms. (author)
Counterfactual quantum cloning without transmitting any physical particles
Guo, Qi; Zhai, Shuqin; Cheng, Liu-Yong; Wang, Hong-Fu; Zhang, Shou
2017-11-01
We propose a counterfactual 1 →2 economical phase-covariant cloning scheme. Compared with the existing protocols using flying qubits, the main difference of the presented scheme is that the cloning can be achieved without transmitting the photon between the two parties. In addition, this counterfactual scheme does not need to construct controlled quantum gates to perform joint logical operations between the cloned qubit and the blank copy. We also numerically evaluate the performance of the present scheme in the practical experiment, which shows this cloning scheme can be implemented with a high success of probability and the fidelity is close to the optimal value in the ideal asymptotic limit.
Physical aspects of pseudo-Hermitian and PT-symmetric quantum mechanics
International Nuclear Information System (INIS)
Mostafazadeh, Ali; Batal, Ahmet
2004-01-01
For a non-Hermitian Hamiltonian H possessing a real spectrum, we introduce a canonical orthonormal basis in which a previously introduced unitary mapping of H to a Hermitian Hamiltonian h takes a simple form. We use this basis to construct the observables O α of the quantum mechanics based on H. In particular, we introduce pseudo-Hermitian position and momentum operators and a pseudo-Hermitian quantization scheme that relates the latter to the ordinary classical position and momentum observables. These allow us to address the problem of determining the conserved probability density and the underlying classical system for pseudo-Hermitian and in particular PT-symmetric quantum systems. As a concrete example we construct the Hermitian Hamiltonian h, the physical observables O α , the localized states and the conserved probability density for the non-Hermitian PT-symmetric square well. We achieve this by employing an appropriate perturbation scheme. For this system, we conduct a comprehensive study of both the kinematical and dynamical effects of the non-Hermiticity of the Hamiltonian on various physical quantities. In particular, we show that these effects are quantum mechanical in nature and diminish in the classical limit. Our results provide an objective assessment of the physical aspects of PT-symmetric quantum mechanics and clarify its relationship with both conventional quantum mechanics and classical mechanics
Nanophysics in graphene: neutrino physics in quantum rings and superlattices.
Fertig, H A; Brey, Luis
2010-12-13
Electrons in graphene at low energy obey a two-dimensional Dirac equation, closely analogous to that of neutrinos. As a result, quantum mechanical effects when the system is confined or subjected to potentials at the nanoscale may be quite different from what happens in conventional electronic systems. In this article, we review recent progress on two systems where this is indeed the case: quantum rings and graphene electrons in a superlattice potential. In the former case, we demonstrate that the spectrum reveals signatures of 'effective time-reversal symmetry breaking', in which the spectra are most naturally interpreted in terms of effective magnetic flux contained in the ring, even when no real flux is present. A one-dimensional superlattice potential is shown to induce strong band-structure changes, allowing the number of Dirac points at zero energy to be manipulated by the strength and/or period of the potential. The emergence of new Dirac points is shown to be accompanied by strong signatures in the conduction properties of the system.
Scale covariant physics: a 'quantum deformation' of classical electrodynamics
International Nuclear Information System (INIS)
Knoll, Yehonatan; Yavneh, Irad
2010-01-01
We present a deformation of classical electrodynamics, continuously depending on a 'quantum parameter', featuring manifest gauge, Poincare and scale covariance. The theory, dubbed extended charge dynamics (ECD), associates a certain length scale with each charge which, due to scale covariance, is an attribute of a solution, not a parameter of the theory. When the EM field experienced by an ECD charge is slowly varying over that length scale, the dynamics of the charge reduces to classical dynamics, its emitted radiation reduces to the familiar Lienard-Wiechert potential and the above length scale is identified as the charge's Compton length. It is conjectured that quantum mechanics describes statistical aspects of ensembles of ECD solutions, much like classical thermodynamics describes statistical aspects of ensembles of classical solutions. A unique 'remote sensing' feature of ECD, supporting that conjecture, is presented, along with an explanation for the illusion of a photon within a classical treatment of the EM field. Finally, a novel conservation law associated with the scale covariance of ECD is derived, indicating that the scale of a solution may 'drift' with time at a constant rate, much like translation covariance implies a uniform drift of the (average) position.
Quantum Optics, Diffraction Theory, and Elementary Particle Physics
CERN. Geneva
2009-01-01
Physical optics has expanded greatly in recent years. Though it remains part of the ancestry of elementary particle physics, there are once again lessons to be learned from it. I shall discuss several of these, including some that have emerged at CERN and Brookhaven.
Can violations of Bell's inequalities be considered as a final proof of quantum physics?
Hénault, François
2013-10-01
Nowadays, it is commonly admitted that the experimental violation of Bell's inequalities that was successfully demonstrated in the last decades by many experimenters, are indeed the ultimate proof of quantum physics and of its ability to describe the whole microscopic world and beyond. But the historical and scientific story may not be envisioned so clearly: it starts with the original paper of Einstein, Podolsky and Rosen (EPR) aiming at demonstrating that the formalism of quantum theory is incomplete. It then goes through the works of D. Bohm, to finally proceed to the famous John Bell's relationships providing an experimental setup to solve the EPR paradox. In this communication is proposed an alternative reading of this history, showing that modern experiments based on correlations between light polarizations significantly deviate from the original spirit of the EPR paper. It is concluded that current experimental violations of Bell's inequalities cannot be considered as an ultimate proof of the completeness of quantum physics models.
«Land of Confusion»: Quantum Physic In IR Theory?
Directory of Open Access Journals (Sweden)
Tatiana A. Alekseeva
2016-01-01
Full Text Available The article deals with the "Quantum mind"hypothesis which has been elaborated in recent works of Alexander Wendt. It is ultimately significant to analyze this hypothesis and to expand on its difficulties and possible inconsistencies given Wendt's credentials in IR theorizing. It allows us to develop a new approach and promising research program on the basis of the hypothesis and its critical reflection. Wendt's quantum physicalism (or holism implies serious philosophical injury and outstanding usage of different science disciplines' apparatus including physics, biology, and psychology. Thought-provoking approach of Wendt boosts researching efforts within the field of political philosophy, world politics and international relations. The main feature of the hypothesis is the idea of quantum nature in social and political processes which appears to be the consequence of epistemological authority of current science. Alexander Wendt proposes several explanations for quantum foundations within the political and social processes including wide-known "agent-structure" dilemma. According to him, invisibility of social structures does not lead to denial of its existence. Firstly, social structures emerge from the space of possibilities and are not directly dependant on material factors. Secondly, invisibility and its acceptance in different areas are parts of science clarification in many areas including quantum physics. The article discuses how quantum physics principles such as particle-wave dualism, superposition and size absoluteness can be useful in social and political studies. This allows us to demonstrate the given hypothesi' potential in research field of social sciences with regard to international relations and world politics.
A Model of the Creative Process Based on Quantum Physics and Vedic Science.
Rose, Laura Hall
1988-01-01
Using tenets from Vedic science and quantum physics, this model of the creative process suggests that the unified field of creation is pure consciousness, and that the development of the creative process within individuals mirrors the creative process within the universe. Rational and supra-rational creative thinking techniques are also described.…
Henriksen, Ellen K.; Bungum, Berit; Angell, Carl; Tellefsen, Catherine W.; Frågåt, Thomas; Bøe, Maria Vetleseter
2014-01-01
In this article, we discuss how quantum physics and relativity can be taught in upper secondary school, in ways that promote conceptual understanding and philosophical reflections. We present the ReleQuant project, in which web-based teaching modules have been developed. The modules address competence aims in the Norwegian national curriculum for…
Exactly renormalizable model in quantum field theory. II. The physical-particle representation
Ruijgrok, Th.W.
1958-01-01
For the simplified model of quantum field theory discussed in a previous paper it is shown how the physical particles can be properly described by means of the so-called asymptotically stationary (a.s.) states. It is possible by formulating the theory in terms of these a.s. states to express it
Vol. 1: Physics of Elementary Particles and Quantum Field Theory. General Problems
International Nuclear Information System (INIS)
Sitenko, A.
1993-01-01
Problems of modern physics and the situation with physical research in Ukraine are considered. Programme of the conference includes scientific and general problems. Its proceedings are published in 6 volumes. The papers presented in this volume refer to elementary particle physics and quantum field theory. The main attention is paid to the following problems: - development of science in Ukraine and its role in the state structures; - modern state of scientific research in Ukraine; - education and training of specialists; - history of Ukrainian physics and contribution of Ukrainian scientists in the world science; - problems of the Ukrainian scientific terminology
Area law for localization-entropy in local quantum physics
Energy Technology Data Exchange (ETDEWEB)
Schroer, Bert [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)]. E-mail: schroer@cbpf.br
2002-02-01
The previously developed algebraic lightfront holography is used in conjunction with the tensor splitting of the chiral theory on the causal horizon. In this way a universal area law for the entanglement entropy of the vacuum relative to the split (tensor factorized) vacuum is obtained. The universality of the area law is a result of the kinematical structure of the properly defined lightfront degrees of freedom. We consider this entropy associated with causal horizon of the wedge algebra in Minkowski spacetime as an analog of the quantum Bekenstein black hole entropy similar to the way in which the Unruh temperature for the wedge algebra may be viewed as an analog in Minkowski spacetime of the Hawking thermal behavior. My more recent preprint hep-th/20202085 presents other aspects of the same problem. (author)
Physics of quantum light emitters in disordered photonic nanostructures
International Nuclear Information System (INIS)
Garcia, P.D.; Lodahl, P.
2017-01-01
Nanophotonics focuses on the control of light and the interaction with matter by the aid of intricate nanostructures. Typically, a photonic nanostructure is carefully designed for a specific application and any imperfections may reduce its performance, i.e., a thorough investigation of the role of unavoidable fabrication imperfections is essential for any application. However, another approach to nanophotonic applications exists where fabrication disorder is used to induce functionalities by enhancing light-matter interaction. Disorder leads to multiple scattering of light, which is the realm of statistical optics where light propagation requires a statistical description. We review here the recent progress on disordered photonic nanostructures and the potential implications for quantum photonics devices. (copyright 2017 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Physics of quantum light emitters in disordered photonic nanostructures
Energy Technology Data Exchange (ETDEWEB)
Garcia, P.D. [Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Barcelona (Spain); Lodahl, P. [Niels Bohr Institute, University of Copenhagen (Denmark)
2017-08-15
Nanophotonics focuses on the control of light and the interaction with matter by the aid of intricate nanostructures. Typically, a photonic nanostructure is carefully designed for a specific application and any imperfections may reduce its performance, i.e., a thorough investigation of the role of unavoidable fabrication imperfections is essential for any application. However, another approach to nanophotonic applications exists where fabrication disorder is used to induce functionalities by enhancing light-matter interaction. Disorder leads to multiple scattering of light, which is the realm of statistical optics where light propagation requires a statistical description. We review here the recent progress on disordered photonic nanostructures and the potential implications for quantum photonics devices. (copyright 2017 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
International Nuclear Information System (INIS)
Dubbers, Dirk; Stoeckmann, Hans-Juergen
2013-01-01
Helps in a compact form to reach good understanding of quantum physics. Shows important analogies between problems across different disciplines. Concise and accurate, written in a readable and lively style. Concentrates on the simplest quantum system which still displays the basic features of quantum theory. Chapters end with a general outlook on multi-level systems. Results are applied to a multitude of topics in modern science, from particle physics and quantum optics to time standards and magnetic resonance imaging. This concise tutorial provides the bachelor student and the practitioner with a short text on quantum physics that allows them to understand a wealth of quantum phenomena based on a compact, well readable, yet still concise and accurate description of nonrelativistic quantum theory. This ''quadrature of the circle'' is achieved by concentrating first on the simplest quantum system that still displays all basic features of quantum theory, namely, a system with only two quantized energy levels. For most readers it is very helpful to understand such simple systems before slowly proceeding to more demanding topics like particle entanglement, quantum chaos, or the use of irreducible tensors. This tutorial does not intend to replace the standard textbooks on quantum mechanics, but will help the average student to understand them, often for the first time.
Quantum field theory and symmetries in nuclear physics
International Nuclear Information System (INIS)
Baldin, A.M.
2000-01-01
Nuclear physics embraces a wide area of knowledge ranging from fundamental problems of matter structure up to the origin of the universe. Applied aspects of this science bear a direct relation to the most urgent problems of people's life - ecology and energetics. The present talk deals with one of these aspects, namely, a possible description of the properties of nuclear matter by means of the methods of modern mathematical physics which N.N. Bogolyubov has greatly contributed to
Physics and engineering of compact quantum dot-based lasers for biophotonics
Rafailov, Edik U
2013-01-01
Written by a team of European experts in the field, this book addresses the physics, the principles, the engineering methods, and the latest developments of efficient and compact ultrafast lasers based on novel quantum-dot structures and devices, as well as their applications in biophotonics. Recommended reading for physicists, engineers, students and lecturers in the fields of photonics, optics, laser physics, optoelectronics, and biophotonics.
Device physics vis-à-vis fundamental physics in Cold War America: the case of quantum optics.
Bromberg, Joan Lisa
2006-06-01
Historians have convincingly shown the close ties U.S. physicists had with the military during the Cold War and have raised the question of whether this alliance affected the content of physics. Some have asserted that it distorted physics, shifting attention from fundamental problems to devices. Yet the papers of physicists in quantum electronics and quantum optics, fields that have been exemplary for those who hold the distortion thesis, show that the same scientists who worked on military devices simultaneously pursued fundamental and foundational topics. This essay examines one such physicist, Marlan O. Scully, with attention to both his extensive foundational studies and the way in which his applied and basic researches played off each other.
Atomic physics. Introduction to quantum physics and structure of the atomic system. 2. ed.
International Nuclear Information System (INIS)
Cagnac, Bernard; Pebay-Peyroula, J.-C.
1975-01-01
This lecture is intended for providing experimental foundations to the basic principles of quantum mechanics, from descriptions of some characteristic experiments which emphasize the limitations of the classical theory. The basic laws that govern the internal structure of atomic systems are exposed (waves and photons, the planetary model and principal quantum number, and the spatial classification of kinetic momenta and magnetic moments). Experimental studies presently in progress are reviewed and their aims are outlined [fr
International Nuclear Information System (INIS)
Xiang Guo-Yong; Guo Guang-Can
2013-01-01
The statistical error is ineluctable in any measurement. Quantum techniques, especially with the development of quantum information, can help us squeeze the statistical error and enhance the precision of measurement. In a quantum system, there are some quantum parameters, such as the quantum state, quantum operator, and quantum dimension, which have no classical counterparts. So quantum metrology deals with not only the traditional parameters, but also the quantum parameters. Quantum metrology includes two important parts: measuring the physical parameters with a precision beating the classical physics limit and measuring the quantum parameters precisely. In this review, we will introduce how quantum characters (e.g., squeezed state and quantum entanglement) yield a higher precision, what the research areas are scientists most interesting in, and what the development status of quantum metrology and its perspectives are. (topical review - quantum information)
Some problems of quantum cosmology and dark matter physics
Wang, Jin
The quantum cosmology is studied of the string universe obtained by embedding the Robertson-Walker metric in the nonlinear sigma model. It was found that initially the universe exists in a series of metastable bound states with the scale factor taking discrete values. Then it tunnels through a barrier and comes out in an inflationary state. This tunneling (or evolution in imaginary time) also has the effect of heating up the matter field so that we have a condition of chaotic inflation. The asymptotic solutions agree with those obtained from the classical Einstein equations. Quantum cosmology was considered of a 4-D universe using the effective action of superstrings. Both Hartle-Hawking and Vilenkin boundary conditions were applied to the solution of Wheeler-DeWitt equation. Under certain conditions (fermions added) the universe was found to tunnel through to the Lorentzian regime from the Euclidean regime and time is dynamically generated. Chudnovsky and Vilenkin's idea was applied to possible existence of cosmic strings in the Sun. Stellar evolution with cosmic strings at solar age gives a radius and luminosity of the star which are in contradiction with observation. The astrophysical bound was studied on the change of gravitational constant with time. It was found that (G/G) less than 10-12yr-1 is the condition that has to be satisfied in order not to cause the conflict with observation. The effect was studied of axions on the steller evolution of a 10 solar mass star model. If the axion mass is larger than .1 ev the star's age is significantly different at late stages, compared to the star without axions. It is argued that if cosmions (or WIMPS) solve the solar neutrino problem, then they must also play an important role in the evolution of low mass star main sequence stars. If they do so, then a simple (long mean free path) model for the interaction of cosmions with baryons leads to changes in the structure of the nuclear-burning core which may in principle
Many-body physics with circuit quantum electrodynamics
International Nuclear Information System (INIS)
Leib, Martin H.
2015-01-01
We present proposals to simulate many-body physics with superconducting circuits. The ''body'' to work with for superconducting circuits is the microwave photon and interaction is induced by the nonlinearity of the Josephson effect. We present two different approaches to simulate Bose-Hubbard physics, one based on a polariton scheme and another with nonlinear resonators. We also present a Dicke-model like simulator for ultrastrongly coupled Josephson junctions to a resonator and show a scheme for implementing long range interactions.
International Nuclear Information System (INIS)
Burkard, Ulrike
2009-01-01
Quantum physics have in the last years developed to an important theme in physics teaching of the gymnasial upper stage. On the side of physics didactics different concepts were developed in order to overcome the specific difficulties in the teaching of quantum physics. Nevertheless the design of the quantum-physics teaching follows still traditional approaches. This work studies the actual situation of the quantum-physics teaching and the possibilities to offer to the teachers conceptional alternatives for the design of the quantum-physics teaching. Thereby among others was studied how a server for multimedia units must be designed structurally and in its contents in order to contribute in the teaching praxis to a further development of the quantum-physics courses. In the development of the server expert knowledge was included. Starting from the status quo of the quantum-physics teaching, which was analyzed in an inquiry of teachers, by means of a Delphi study possibilities for the improvement of the quality of the quantum-physics teaching by the application of multimedia were determined. To this belongs beside the identification of suited theme fields also the gathering of methodical tips and possible conceptional further developments of the quantum-physics teaching. The results of the study entered directly in the parralely running development of the media server. So the server offers to each medium didactical explanations about learning goals, learning conditions etc. and makes proposals for a possible application scenario of each multimedial unit. Furthermore pupil activating problems are offered, which can be worked out by means of the medium. In these additional offers lies an essential didactical advantage of the server against conventional link list or search engines
Nonperturbative Quantum Physics from Low-Order Perturbation Theory.
Mera, Héctor; Pedersen, Thomas G; Nikolić, Branislav K
2015-10-02
The Stark effect in hydrogen and the cubic anharmonic oscillator furnish examples of quantum systems where the perturbation results in a certain ionization probability by tunneling processes. Accordingly, the perturbed ground-state energy is shifted and broadened, thus acquiring an imaginary part which is considered to be a paradigm of nonperturbative behavior. Here we demonstrate how the low order coefficients of a divergent perturbation series can be used to obtain excellent approximations to both real and imaginary parts of the perturbed ground state eigenenergy. The key is to use analytic continuation functions with a built-in singularity structure within the complex plane of the coupling constant, which is tailored by means of Bender-Wu dispersion relations. In the examples discussed the analytic continuation functions are Gauss hypergeometric functions, which take as input fourth order perturbation theory and return excellent approximations to the complex perturbed eigenvalue. These functions are Borel consistent and dramatically outperform widely used Padé and Borel-Padé approaches, even for rather large values of the coupling constant.
Uncertainty in the classroom—teaching quantum physics
International Nuclear Information System (INIS)
Johansson, K E; Milstead, D
2008-01-01
The teaching of the Heisenberg uncertainty principle provides one of those rare moments when science appears to contradict everyday life experiences, sparking the curiosity of the interested student. Written at a level appropriate for an able high school student, this article provides ideas for introducing the uncertainty principle and showing how it can be used to elucidate many topics in modern physics
Non-Hermitian quantum mechanics and localization in physical systems
International Nuclear Information System (INIS)
Hatano, Naomichi
1998-01-01
Recent studies on a delocalization phenomenon of a non-Hermitian random system is reviewed. The complex spectrum of the system indicates delocalization transition of its eigenfunctions. It is emphasized that the delocalization is related to various physical phenomena such as flux-line pinning in superconductors and population biology of bacteria colony
A criticism to the fundamental principles of physics: The problem of the quantum measurement (I)
International Nuclear Information System (INIS)
Mormontoy Cardenas, Oscar; Marquez Jacome, Mateo
2008-01-01
The wave packet model collapse debt to extremely fast fluctuations of quantum field leads to interpreting the phase speed of the harmonic waves that compose the packet, as the speed of time flux. If it consider that harmonics waves keep different phases, the waves packet scattered almost instantly and, as consequence of that, allows the possibility of the quantum system energy it is measure with exactitude absolute in given time. These results induce to think that the time would being a superforce which would determine finally the events of universe and being responsible of the intrinsic pulsations observable in the physics systems. (author)
Physical model for the generation of ideal resources in multipartite quantum networking
International Nuclear Information System (INIS)
Ciccarello, F.; Zarcone, M.; Paternostro, M.; Bose, S.; Browne, D. E.; Palma, G. M.
2010-01-01
We propose a physical model for generating multipartite entangled states of spin-s particles that have important applications in distributed quantum information processing. Our protocol is based on a process where mobile spins induce the interaction among remote scattering centers. As such, a major advantage lies in the management of stationary and well-separated spins. Among the generable states, there is a class of N-qubit singlets allowing for optimal quantum telecloning in a scalable and controllable way. We also show how to prepare Aharonov, W, and Greenberger-Horne-Zeilinger states.
Research and pedagogy a history of quantum physics through its textbooks
Navarro, Jaume
2013-01-01
Historians of quantum physics and early quantum mechanics have seldom paid attention to the ways the new theory was integrated in physics textbooks, perhaps taking for granted that novelties in science can only be taught once they are fully understood and generally accepted. The essays in this volume challenge this view by studying some of the early books and textbooks in which quantum theory was first introduced. By so doing, the authors show the many ways books and textbooks embody pedagogical and research practices in certain local environments (geographical, disciplinary, in terms of expertise, etc.), as well as the circular feedback between research and pedagogy. Textbooks can become the subject of a history of early quantum physics since the very process of writing a textbook, (i.e., of trying to organise a new doctrine to the newcomer in an accessible way), together with its life as an object that is issued, used, changed, and abandoned, incorporates many of the tensions between research and pedagogy....
Baumann, Gerd
2005-01-01
Mathematica for Theoretical Physics: Electrodynamics, Quantum Mechanics, General Relativity, and Fractals This second edition of Baumann's Mathematica® in Theoretical Physics shows readers how to solve physical problems and deal with their underlying theoretical concepts while using Mathematica® to derive numeric and symbolic solutions. Each example and calculation can be evaluated by the reader, and the reader can change the example calculations and adopt the given code to related or similar problems. The second edition has been completely revised and expanded into two volumes: The first volume covers classical mechanics and nonlinear dynamics. Both topics are the basis of a regular mechanics course. The second volume covers electrodynamics, quantum mechanics, relativity, and fractals and fractional calculus. New examples have been added and the representation has been reworked to provide a more interactive problem-solving presentation. This book can be used as a textbook or as a reference work, by student...
Castagnoli, Giuseppe
2018-03-01
The usual representation of quantum algorithms, limited to the process of solving the problem, is physically incomplete. We complete it in three steps: (i) extending the representation to the process of setting the problem, (ii) relativizing the extended representation to the problem solver to whom the problem setting must be concealed, and (iii) symmetrizing the relativized representation for time reversal to represent the reversibility of the underlying physical process. The third steps projects the input state of the representation, where the problem solver is completely ignorant of the setting and thus the solution of the problem, on one where she knows half solution (half of the information specifying it when the solution is an unstructured bit string). Completing the physical representation shows that the number of computation steps (oracle queries) required to solve any oracle problem in an optimal quantum way should be that of a classical algorithm endowed with the advanced knowledge of half solution.
Quantum simulation of 2D topological physics in a 1D array of optical cavities.
Luo, Xi-Wang; Zhou, Xingxiang; Li, Chuan-Feng; Xu, Jin-Shi; Guo, Guang-Can; Zhou, Zheng-Wei
2015-07-06
Orbital angular momentum of light is a fundamental optical degree of freedom characterized by unlimited number of available angular momentum states. Although this unique property has proved invaluable in diverse recent studies ranging from optical communication to quantum information, it has not been considered useful or even relevant for simulating nontrivial physics problems such as topological phenomena. Contrary to this misconception, we demonstrate the incredible value of orbital angular momentum of light for quantum simulation by showing theoretically how it allows to study a variety of important 2D topological physics in a 1D array of optical cavities. This application for orbital angular momentum of light not only reduces required physical resources but also increases feasible scale of simulation, and thus makes it possible to investigate important topics such as edge-state transport and topological phase transition in a small simulator ready for immediate experimental exploration.
Quantum theory from a nonlinear perspective Riccati equations in fundamental physics
Schuch, Dieter
2018-01-01
This book provides a unique survey displaying the power of Riccati equations to describe reversible and irreversible processes in physics and, in particular, quantum physics. Quantum mechanics is supposedly linear, invariant under time-reversal, conserving energy and, in contrast to classical theories, essentially based on the use of complex quantities. However, on a macroscopic level, processes apparently obey nonlinear irreversible evolution equations and dissipate energy. The Riccati equation, a nonlinear equation that can be linearized, has the potential to link these two worlds when applied to complex quantities. The nonlinearity can provide information about the phase-amplitude correlations of the complex quantities that cannot be obtained from the linearized form. As revealed in this wide ranging treatment, Riccati equations can also be found in many diverse fields of physics from Bose-Einstein-condensates to cosmology. The book will appeal to graduate students and theoretical physicists interested in ...
International Nuclear Information System (INIS)
Vogd, Werner
2014-01-01
The quantum theory represents one of the most fastidious and successful theory projects of the history of mankind. It is one, if not the universal theory of physics. The history of its interpretation and the discussion affects however by far more than only the field of theoretical physics. Such theory approach destroys ontological certainty. It calls the observer in question, and it lets us anticipate, what is to be expected, if we are employed in other fields with complex phenomena, which are infected with the observer problematics. As transclassical physics the quantum theory is so to say built on ''worlds without ground'' and disappoints by this the hope to be able to set themselves free from mind questions by physics or mathematics. Homologuously to the top forms of mystic reflexion the discussion about the interpretation of quantum physics can mediate an idea, what the mystery of the conditioned coproduction of system and environment - reflexion and world - can mean for us and possibly help us to become homelike in worlds without grounds. Hereby it becomes clear, that highly driven theory, which solves itself in its abstractions in a high degree from the live-worldly reality, stands not in contradiction to the possibility of knowledge of the world. On the contrary, at first a theory creation sufficiently elaborated and endowed with own internally conditioned consistency constraints represents the condition for the possibility of reflexion and gain of knowledge.
Predicting the valley physics of silicon quantum dots directly from a device layout
Gamble, John King; Harvey-Collard, Patrick; Jacobson, N. Tobias; Bacewski, Andrew D.; Nielsen, Erik; Montaño, Inès; Rudolph, Martin; Carroll, Malcolm S.; Muller, Richard P.
Qubits made from electrostatically-defined quantum dots in Si-based systems are excellent candidates for quantum information processing applications. However, the multi-valley structure of silicon's band structure provides additional challenges for the few-electron physics critical to qubit manipulation. Here, we present a theory for valley physics that is predictive, in that we take as input the real physical device geometry and experimental voltage operation schedule, and with minimal approximation compute the resulting valley physics. We present both effective mass theory and atomistic tight-binding calculations for two distinct metal-oxide-semiconductor (MOS) quantum dot systems, directly comparing them to experimental measurements of the valley splitting. We conclude by assessing these detailed simulations' utility for engineering desired valley physics in future devices. Sandia is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US Department of Energy's National Nuclear Security Administration under Contract No. DE-AC04-94AL85000. The authors gratefully acknowledge support from the Sandia National Laboratories Truman Fellowship Program, which is funded by the Laboratory Directed Research and Development (LDRD) Program.
Many body quantum physics at the condensed matter
International Nuclear Information System (INIS)
Llano, M. de
1981-01-01
The non-relativistic, continuous (as opposed to spin) many-body problem as it relates to condensed matter at absolute zero temperature is reviewed in simple, non-technical terms, mainly from the standpoint of infinite order perturbation theory, for physical systems where all the particles have the same mass but which otherwise interact with arbitrary short- or long-ranged two-body forces. (author)
International Nuclear Information System (INIS)
Zeidler, Eberhard
2009-01-01
This is the first volume of a modern introduction to quantum field theory which addresses both mathematicians and physicists, at levels ranging from advanced undergraduate students to professional scientists. The book bridges the acknowledged gap between the different languages used by mathematicians and physicists. For students of mathematics the author shows that detailed knowledge of the physical background helps to motivate the mathematical subjects and to discover interesting interrelationships between quite different mathematical topics. For students of physics, fairly advanced mathematics is presented, which goes beyond the usual curriculum in physics. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Zeidler, Eberhard [Max-Planck-Institut fuer Mathematik in den Naturwissenschaften, Leipzig (Germany)
2009-07-01
This is the first volume of a modern introduction to quantum field theory which addresses both mathematicians and physicists, at levels ranging from advanced undergraduate students to professional scientists. The book bridges the acknowledged gap between the different languages used by mathematicians and physicists. For students of mathematics the author shows that detailed knowledge of the physical background helps to motivate the mathematical subjects and to discover interesting interrelationships between quite different mathematical topics. For students of physics, fairly advanced mathematics is presented, which goes beyond the usual curriculum in physics. (orig.)
Can Quantum-Mechanical Description of Physical Reality Be Considered Correct?
Brassard, Gilles; Méthot, André Allan
2010-04-01
In an earlier paper written in loving memory of Asher Peres, we gave a critical analysis of the celebrated 1935 paper in which Einstein, Podolsky and Rosen (EPR) challenged the completeness of quantum mechanics. There, we had pointed out logical shortcomings in the EPR paper. Now, we raise additional questions concerning their suggested program to find a theory that would “provide a complete description of the physical reality”. In particular, we investigate the extent to which the EPR argumentation could have lead to the more dramatic conclusion that quantum mechanics is in fact incorrect. With this in mind, we propose a speculation, made necessary by a logical shortcoming in the EPR paper caused by the lack of a necessary condition for “elements of reality”, and surmise that an eventually complete theory would either be inconsistent with quantum mechanics, or would at least violate Heisenberg’s Uncertainty Principle.
Electron spin resonance and spin-valley physics in a silicon double quantum dot.
Hao, Xiaojie; Ruskov, Rusko; Xiao, Ming; Tahan, Charles; Jiang, HongWen
2014-05-14
Silicon quantum dots are a leading approach for solid-state quantum bits. However, developing this technology is complicated by the multi-valley nature of silicon. Here we observe transport of individual electrons in a silicon CMOS-based double quantum dot under electron spin resonance. An anticrossing of the driven dot energy levels is observed when the Zeeman and valley splittings coincide. A detected anticrossing splitting of 60 MHz is interpreted as a direct measure of spin and valley mixing, facilitated by spin-orbit interaction in the presence of non-ideal interfaces. A lower bound of spin dephasing time of 63 ns is extracted. We also describe a possible experimental evidence of an unconventional spin-valley blockade, despite the assumption of non-ideal interfaces. This understanding of silicon spin-valley physics should enable better control and read-out techniques for the spin qubits in an all CMOS silicon approach.
Introductory quantum mechanics a traditional approach emphasizing connections with classical physics
Berman, Paul R
2018-01-01
This book presents a basic introduction to quantum mechanics at the undergraduate level. Depending on the choice of topics, it can be used for a one-semester or two-semester course. An attempt has been made to anticipate the conceptual problems students encounter when they first study quantum mechanics. Wherever possible, examples are given to illustrate the underlying physics associated with the mathematical equations of quantum mechanics. To this end, connections are made with corresponding phenomena in classical mechanics and electromagnetism. The problems at the end of each chapter are intended to help students master the course material and to explore more advanced topics. Many calculations exploit the extraordinary capabilities of computer programs such as Mathematica, MatLab, and Maple. Students are urged to use these programs, just as they had been urged to use calculators in the past. The treatment of various topics is rather complete, in that most steps in derivations are included. Several of the ch...
Nori, Franco
2012-02-01
This talk will present an overview of some of our recent results on atomic physics and quantum optics using superconducting circuits. Particular emphasis will be given to photons interacting with qubits, interferometry, the Dynamical Casimir effect, and also studying Majorana fermions using superconducting circuits.[4pt] References available online at our web site:[0pt] J.Q. You, Z.D. Wang, W. Zhang, F. Nori, Manipulating and probing Majorana fermions using superconducting circuits, (2011). Arxiv. J.R. Johansson, G. Johansson, C.M. Wilson, F. Nori, Dynamical Casimir effect in a superconducting coplanar waveguide, Phys. Rev. Lett. 103, 147003 (2009). [0pt] J.R. Johansson, G. Johansson, C.M. Wilson, F. Nori, Dynamical Casimir effect in superconducting microwave circuits, Phys. Rev. A 82, 052509 (2010). [0pt] C.M. Wilson, G. Johansson, A. Pourkabirian, J.R. Johansson, T. Duty, F. Nori, P. Delsing, Observation of the Dynamical Casimir Effect in a superconducting circuit. Nature, in press (Nov. 2011). P.D. Nation, J.R. Johansson, M.P. Blencowe, F. Nori, Stimulating uncertainty: Amplifying the quantum vacuum with superconducting circuits, Rev. Mod. Phys., in press (2011). [0pt] J.Q. You, F. Nori, Atomic physics and quantum optics using superconducting circuits, Nature 474, 589 (2011). [0pt] S.N. Shevchenko, S. Ashhab, F. Nori, Landau-Zener-Stuckelberg interferometry, Phys. Reports 492, 1 (2010). [0pt] I. Buluta, S. Ashhab, F. Nori. Natural and artificial atoms for quantum computation, Reports on Progress in Physics 74, 104401 (2011). [0pt] I.Buluta, F. Nori, Quantum Simulators, Science 326, 108 (2009). [0pt] L.F. Wei, K. Maruyama, X.B. Wang, J.Q. You, F. Nori, Testing quantum contextuality with macroscopic superconducting circuits, Phys. Rev. B 81, 174513 (2010). [0pt] J.Q. You, X.-F. Shi, X. Hu, F. Nori, Quantum emulation of a spin system with topologically protected ground states using superconducting quantum circuit, Phys. Rev. A 81, 063823 (2010).
Dubbers, Dirk
2013-01-01
This concise tutorial provides the bachelor student and the practitioner with a short text on quantum physics that allows them to understand a wealth of quantum phenomena based on a compact, well readable, yet still concise and accurate description of nonrelativistic quantum theory. This “quadrature of the circle” is achieved by concentrating first on the simplest quantum system that still displays all basic features of quantum theory, namely, a system with only two quantized energy levels. For most readers it is very helpful to understand such simple systems before slowly proceeding to more demanding topics like particle entanglement, quantum chaos, or the use of irreducible tensors. This tutorial does not intend to replace the standard textbooks on quantum mechanics, but will help the average student to understand them, often for the first time.
International Nuclear Information System (INIS)
Chen, Pisin
2002-01-01
The 18th Advanced ICFA Beam Dynamics Workshop on ''Quantum Aspects of Beam Physics'' was held from October 15 to 20, 2000, in Capri, Italy. This was the second workshop under the same title. The first one was held in Monterey, California, in January, 1998. Following the footstep of the first meeting, the second one in Capri was again a tremendous success, both scientifically and socially. About 70 colleagues from astrophysics, atomic physics, beam physics, condensed matter physics, particle physics, and general relativity gathered to update and further explore the topics covered in the Monterey workshop. Namely, the following topics were actively discussed: (1) Quantum Fluctuations in Beam Dynamics; (2) Photon-Electron Interaction in Beam handling; (3) Physics of Condensed Beams; (4) Beam Phenomena under Strong Fields; (5) Quantum Methodologies in Beam Physics. In addition, there was a newly introduced subject on Astro-Beam Physics and Laboratory Astrophysics
International Nuclear Information System (INIS)
Marshman, Emily; Singh, Chandralekha
2017-01-01
A solid grasp of the probability distributions for measuring physical observables is central to connecting the quantum formalism to measurements. However, students often struggle with the probability distributions of measurement outcomes for an observable and have difficulty expressing this concept in different representations. Here we first describe the difficulties that upper-level undergraduate and PhD students have with the probability distributions for measuring physical observables in quantum mechanics. We then discuss how student difficulties found in written surveys and individual interviews were used as a guide in the development of a quantum interactive learning tutorial (QuILT) to help students develop a good grasp of the probability distributions of measurement outcomes for physical observables. The QuILT strives to help students become proficient in expressing the probability distributions for the measurement of physical observables in Dirac notation and in the position representation and be able to convert from Dirac notation to position representation and vice versa. We describe the development and evaluation of the QuILT and findings about the effectiveness of the QuILT from in-class evaluations. (paper)
Sanghera, Paul
2011-01-01
Presenting quantum physics for the non-physicists, Quantum Physics for Scientists and Technologists is a self-contained, cohesive, concise, yet comprehensive, story of quantum physics from the fields of science and technology, including computer science, biology, chemistry, and nanotechnology. The authors explain the concepts and phenomena in a practical fashion with only a minimum amount of math. Examples from, and references to, computer science, biology, chemistry, and nanotechnology throughout the book make the material accessible to biologists, chemists, computer scientists, and non-techn
Teaching quantum physics by the sum over paths approach and GeoGebra simulations
International Nuclear Information System (INIS)
Malgieri, M; Onorato, P; De Ambrosis, A
2014-01-01
We present a research-based teaching sequence in introductory quantum physics using the Feynman sum over paths approach. Our reconstruction avoids the historical pathway, and starts by reconsidering optics from the standpoint of the quantum nature of light, analysing both traditional and modern experiments. The core of our educational path lies in the treatment of conceptual and epistemological themes, peculiar of quantum theory, based on evidence from quantum optics, such as the single photon Mach–Zehnder and Zhou–Wang–Mandel experiments. The sequence is supported by a collection of interactive simulations, realized in the open source GeoGebra environment, which we used to assist students in learning the basics of the method, and help them explore the proposed experimental situations as modeled in the sum over paths perspective. We tested our approach in the context of a post-graduate training course for pre-service physics teachers; according to the data we collected, student teachers displayed a greatly improved understanding of conceptual issues, and acquired significant abilities in using the sum over path method for problem solving. (paper)
International Nuclear Information System (INIS)
Fabre, Claude
2003-01-01
This document contains two nearly identical courses on the interaction between matter and electromagnetic radiation. The second one addresses a few more issues in sub-paragraphs, but follows the same organisation and plan. A first part addresses tools in quantum optics. It presents phenomenological approaches (the Lorentz and Einstein models), the semi-conventional approach (isolated atom, effect of the environment with the Bloch equations, interaction with a non-monochromatic field, oscillator force), the quantum description of the free electromagnetic field (corpuscular aspect of the thermal radiation field, decomposition of the conventional electromagnetic field into modes, quantification of free radiation, radiation kinetic moment and pulse, radiation stationary states, value of the electric field in a quantum state), the interaction between atom and quantum field (interaction Hamiltonian, interaction process, photo-detection). The second part addresses some phenomena of quantum optics such as spontaneous emission, quasi-resonant interactions in two-level systems, three-level systems, fluctuations and correlations in the matter-radiation interaction. Appendices contain elements on atom structure, and on the density matrix
International Nuclear Information System (INIS)
Marcer, Peter J.; Rowlands, Peter
2010-01-01
Further evidence is presented in favour of the computational paradigm, conceived and constructed by Rowlands and Diaz, as detailed in Rowlands' book Zero to Infinity (2007), and in particular the authors' paper 'The Grammatical Universe: the Laws of Thermodynamics and Quantum Entanglement'. The paradigm, which has isomorphic group and algebraic quantum mechanical language interpretations, not only predicts the well-established facts of quantum physics, the periodic table, chemistry / valence and of molecular biology, whose understanding it extends; it also provides an elegant, simple solution to the unresolved quantum measurement problem. In this fundamental paradigm, all the computational constructs / predictions that emerge, follow from the simple fact, that, as in quantum mechanics, the wave function is defined only up to an arbitrary fixed phase. This fixed phase provides a simple physical understanding of the quantum vacuum in quantum field theory, where only relative phases, known to be able to encode 3+1 relativistic space-time geometries, can be measured. It is the arbitrary fixed measurement standard, against which everything that follows is to be measured, even though the standard itself cannot be, since nothing exists against which to measure it. The standard, as an arbitrary fixed reference phase, functions as the holographic basis for a self-organized universal quantum process of emergent novel fermion states of matter where, following each emergence, the arbitrary standard is re-fixed anew so as to provide a complete history / holographic record or hologram of the current fixed past, advancing an unending irreversible evolution, such as is the evidence of our senses. The fermion states, in accord with the Pauli exclusion principle, each correspond to a unique nilpotent symbol in the infinite alphabet (which specifies the grammar in this nilpotent universal computational rewrite system (NUCRS) paradigm); and the alphabet, as Hill and Rowlands
The spin-s quantum Heisenberg ferromagnetic models in the physical magnon theory
International Nuclear Information System (INIS)
Liu, B.-G.; Pu, F.-C.
2001-01-01
The spin-s quantum Heisenberg ferromagnetic model is investigated in the physical magnon theory. The effect of the extra unphysical magnon states on every site is completely removed in the magnon Hamiltonian and during approximation procedure so that the condition †n i a n i >=0(n≥2s+1) is rigorously satisfied. The physical multi-magnon occupancy †n i a n i >(1≤n≤2s) is proportional to T 3n/2 at low temperature and is equivalent to 1/(2s+1) at the Curie temperature. The magnetization not only unified but also well-behaved from zero temperature to Curie temperature is obtained in the framework of the magnon theory for the spin-s quantum Heisenberg ferromagnetic model. The ill-behaved magnetizations at high temperature in earlier magnon theories are completely corrected. The relation of magnon (spin wave) theory with spin-operator decoupling theory is clearly understood
On the physical nonexistence of signals going backwards in time, and quantum mechanics
International Nuclear Information System (INIS)
Garuccio, A.; Maccarrone, G.D.
1980-01-01
With regard to the recent results of new experiments about the EPR-paradox, which seem to disagree with Bell inequality and appear to confirm quantum mechanics, some theoretical interpretations have been proposed. In this letter, it is shown that the interpretations invoking transmission of signals into the past do not seem to be physically acceptable. The positive role of the ''Reinterpretation Principle'' (for an orthodox reinterpretation of the ''advanced solutions'') is in particular stressed. (author)
Effects of the quantum vacuum in particle physics and cosmology
Energy Technology Data Exchange (ETDEWEB)
Smirnov, Juri
2014-11-26
In this work we investigate numerous effects of virtual particles on processes relevant for particle physics and cosmology. A central question is, whether radiative spontaneous electroweak symmetry breaking can be combined with neutrino mass generation, we find that the answer is affirmative. We discuss the implication of the RSSB on the neutrino mass phenomenology and low-energy observables. Furthermore, by comparing the models to experimental data we find that several anomalies in the present observations favour particular scenarios over the pure Standard Model hypothesis. We are able to show, that the presence of sterile neutrinos with active-sterile mixing of order 10{sup -3} and masses in the TeV range leads to a reduced invisible decay width of the Z-boson and can bring the NuTeV observations in agreement with theoretical expectations. The models we discuss naturally incorporate long lived particles which can serve as dark matter candidates and we investigate this phenomenologically. We find that the combination of the requirements leads to interesting constraints on the model and parameter space. We find that loop induced electromagnetic moments for the neutral dark matter candidates, lead to interactions with charged particles. We use this and derive new constraints from existing XENON100 and LUX data. In addition we study how vacuum effects can backreact on a given geometry in electromagnetism and semiclassical gravity. We find that in the case of gravity the conformal set up plays a special role and indicate several ideas for further investigation of this topic.
Energy Technology Data Exchange (ETDEWEB)
Niederle, J; Bednar, M; Bicak, J
1987-01-01
The conference, the fourth in the series of conferences on this subject, was held at the Bechyne castle (Czechoslovakia) on June 23-27, 1986, and was attended by about 100 theoreticians from 15 countries. The conference was organized by the Institute of Physics of the Czechoslovak Academy of Sciences in Prague together with the Faculties of Mathematics and Physics of the Charles University, Prague, and of the Comenius University, Bratislava, the Faculty of Nuclear Science and Physical Engineering of the Czech Techical University, Prague, with the Institute of Physics of the Electro-Physical Research Centre of the Slovak Academy of Sciences, Bratislava, and the Institute of Nuclear Physics of the Czechoslovak Academy of Sciences in Rez. It was sponsored by the International Union for Pure and Applied Physics, the International Association of Mathematical Physics and the Physical Scientific Section of the Union of Czechoslovak Mathematicians and Physicists. The main subjects discussed at the conference were: supersymmetries, supergravity and superstring theories; quantum field theory and in particular gauge theories, theories on lattices, renormalization; selected topics in non-linear equations, scattering theory and quantization. Details are given in the attached program. The proceedings include invited talks and contributions presented respectively at the morning and afternoon sessions of the conference. The main part of the proceedings will be published in the Czechoslovak Journal of Physics v. 37(1987), nos. 3,4 and 9.
International Nuclear Information System (INIS)
Niederle, J.; Bednar, M.; Bicak, J.
1987-01-01
The conference, the fourth in the series of conferences on this subject, was held at the Bechyne castle (Czechoslovakia) on June 23-27, 1986, and was attended by about 100 theoreticians from 15 countries. The conference was organized by the Institute of Physics of the Czechoslovak Academy of Sciences in Prague together with the Faculties of Mathematics and Physics of the Charles University, Prague, and of the Comenius University, Bratislava, the Faculty of Nuclear Science and Physical Engineering of the Czech Techical University, Prague, with the Institute of Physics of the Electro-Physical Research Centre of the Slovak Academy of Sciences, Bratislava, and the Institute of Nuclear Physics of the Czechoslovak Academy of Sciences in Rez. It was sponsored by the International Union for Pure and Applied Physics, the International Association of Mathematical Physics and the Physical Scientific Section of the Union of Czechoslovak Mathematicians and Physicists. The main subjects discussed at the conference were: supersymmetries, supergravity and superstring theories; quantum field theory and in particular gauge theories, theories on lattices, renormalization; selected topics in non-linear equations, scattering theory and quantization. Details are given in the attached program. The proceedings include invited talks and contributions presented respectively at the morning and afternoon sessions of the conference. The main part of the proceedings will be published in the Czechoslovak Journal of Physics v. 37(1987), nos. 3,4 and 9. (author)
International Nuclear Information System (INIS)
Kushnirenko, A.N.
1989-01-01
An attempt was made to substantiate statistical physics from the viewpoint of many-body quantum mechanics in the representation of occupation numbers. This approach enabled to develop the variation method for solution of stationary and nonstationary nonequilibrium problems
International Nuclear Information System (INIS)
Rangelov, J.M.
1986-01-01
An electron model is proposed explaining the physical reasons for its nonrelativistic quantum-mechanical behaviour, the origin of its own mechanical and magnetic momentum and field energy. As an example the main electron state in hydrogen atom is obtained
Böhm, Arno; Koizumi, Hiroyasu; Niu, Qian; Zwanziger, Joseph
2003-01-01
Aimed at graduate physics and chemistry students, this is the first comprehensive monograph covering the concept of the geometric phase in quantum physics from its mathematical foundations to its physical applications and experimental manifestations It contains all the premises of the adiabatic Berry phase as well as the exact Anandan-Aharonov phase It discusses quantum systems in a classical time-independent environment (time dependent Hamiltonians) and quantum systems in a changing environment (gauge theory of molecular physics) The mathematical methods used are a combination of differential geometry and the theory of linear operators in Hilbert Space As a result, the monograph demonstrates how non-trivial gauge theories naturally arise and how the consequences can be experimentally observed Readers benefit by gaining a deep understanding of the long-ignored gauge theoretic effects of quantum mechanics and how to measure them
Dr. Bertlmann's socks. How quantum physics changes our picture of ther world
International Nuclear Information System (INIS)
Malin, S.
2006-01-01
Quantum mechanics, which has together with relativity theory revolutionized physics, is for many people always yet a book with seven seals. Too difficult, too strange, too far? Far from the mark. Shimon Malin launches his reader by a pedagogical trick on a knowledge-rich discovery journey. Two fictive astronauts, The intelligent Julie and the lightly stupid Peter discuss with the real author the progress of the book. Thereby they arrive farly beyond pure natural science at the philosophical question, which means the paradigam change in physics for our picture of the world
Whiffen, D H
2013-01-01
Expression of Results in Quantum Chemistry recommends the appropriate insertion of physical constants in the output information of a theoretical paper in order to make the numerical end results of theoretical work easily transformed to SI units by the reader. The acceptance of this recommendation would circumvent the need for a set of atomic units each with its own symbol and name. It is the traditional use of the phrase """"atomic units"""" in this area which has obscured the real problem. The four SI dimensions of length, mass, time, and current require four physical constants to be permitte
Optically Driven Spin Based Quantum Dots for Quantum Computing - Research Area 6 Physics 6.3.2
2015-12-15
SECURITY CLASSIFICATION OF: This program conducted experimental and theoretical research aimed at developing an optically driven quantum dot quantum ...computer, where, the qubit is the spin of the electron trapped in a self-assembled quantum dot in InAs. Optical manipulation using the trion state...reports. In this reporting period, we discovered the nuclear spin quieting first discovered in 2008 is present in vertically coupled quantum dots but
Exploring 4D quantum Hall physics with a 2D topological charge pump
Lohse, Michael; Schweizer, Christian; Price, Hannah M.; Zilberberg, Oded; Bloch, Immanuel
2018-01-01
The discovery of topological states of matter has greatly improved our understanding of phase transitions in physical systems. Instead of being described by local order parameters, topological phases are described by global topological invariants and are therefore robust against perturbations. A prominent example is the two-dimensional (2D) integer quantum Hall effect: it is characterized by the first Chern number, which manifests in the quantized Hall response that is induced by an external electric field. Generalizing the quantum Hall effect to four-dimensional (4D) systems leads to the appearance of an additional quantized Hall response, but one that is nonlinear and described by a 4D topological invariant—the second Chern number. Here we report the observation of a bulk response with intrinsic 4D topology and demonstrate its quantization by measuring the associated second Chern number. By implementing a 2D topological charge pump using ultracold bosonic atoms in an angled optical superlattice, we realize a dynamical version of the 4D integer quantum Hall effect. Using a small cloud of atoms as a local probe, we fully characterize the nonlinear response of the system via in situ imaging and site-resolved band mapping. Our findings pave the way to experimentally probing higher-dimensional quantum Hall systems, in which additional strongly correlated topological phases, exotic collective excitations and boundary phenomena such as isolated Weyl fermions are predicted.
On an entanglement measure in quantum physics: geometric aspects of density matrices
Energy Technology Data Exchange (ETDEWEB)
Franco, D.H.T.; Cima, O.M.D.; Silva, S.L.L. [Universidade Federal de Vicosa - UFV, MG (Brazil)
2013-07-01
Full text: The study of entanglement would be justified simply by its theoretical interest, given that this phenomenon since its inception, casts important questions on the basis of a fundamental character of the building that is quantum mechanics. Moreover,the entanglement has been an indispensable ingredient in the field of quantum computing (processing and transmission of information) and also in condensed matter physics (in the understanding of quantum phase transitions). In this work we present and discuss some ways to characterize both quantitatively and qualitatively entanglement. In particular, we aim to introduce and apply the method developed by Dahl et al. [1]. This method determines the distance from the nearest separable state of the state of interest, since this distance may be used to measure the degree of entanglement of the system of interest. We consider a separable state by state with only classical correlations, i.e a non-entangled, non-separable states which are said entangled. Quantum entanglement has been shown, also, a very useful tool in the study of superconductivity. We aim to study the relationship between the phase transition of superconductivity and the spin entanglement of the Cooper pairs. [1] G. Dahl, J. M. Leinaas, J. Myrheim, and E. Ovrum. Linear Algebra and its application, 420:711-725, 2007 (author)
Exploring 4D quantum Hall physics with a 2D topological charge pump.
Lohse, Michael; Schweizer, Christian; Price, Hannah M; Zilberberg, Oded; Bloch, Immanuel
2018-01-03
The discovery of topological states of matter has greatly improved our understanding of phase transitions in physical systems. Instead of being described by local order parameters, topological phases are described by global topological invariants and are therefore robust against perturbations. A prominent example is the two-dimensional (2D) integer quantum Hall effect: it is characterized by the first Chern number, which manifests in the quantized Hall response that is induced by an external electric field. Generalizing the quantum Hall effect to four-dimensional (4D) systems leads to the appearance of an additional quantized Hall response, but one that is nonlinear and described by a 4D topological invariant-the second Chern number. Here we report the observation of a bulk response with intrinsic 4D topology and demonstrate its quantization by measuring the associated second Chern number. By implementing a 2D topological charge pump using ultracold bosonic atoms in an angled optical superlattice, we realize a dynamical version of the 4D integer quantum Hall effect. Using a small cloud of atoms as a local probe, we fully characterize the nonlinear response of the system via in situ imaging and site-resolved band mapping. Our findings pave the way to experimentally probing higher-dimensional quantum Hall systems, in which additional strongly correlated topological phases, exotic collective excitations and boundary phenomena such as isolated Weyl fermions are predicted.
Physics and necessity rationalist pursuits from the Cartesian past to the quantum present
Darrigol, Olivier
2014-01-01
Can we prove the necessity of our best physical theories by rational means, without appeal to experience? This book recounts a few ingenious attempts to derive physical theories by reason only, beginning with Descartes' geometric construction of the world, and finishing with recent derivations of quantum mechanics from natural axioms. Deductions based on theological, metaphysical, or transcendental arguments are worth remembering for the ways they motivated and structured physical theory, even though we would now criticize their excessive confidence in the power of the mind. Other deductions more modestly relied on criteria for the comprehensibility of nature, including forms of measurability, causality, homogeneity, and correspondence. The central thesis of this book is that such criteria, when properly applied to idealized systems, effectively determine some of our most important theories as well as the mathematical character of the laws of physics. The relevant arguments are not purely rational, because on...
Tutorium quantum mechanics. By an experienced tutor for students of physics and mathematics
International Nuclear Information System (INIS)
Schwindt, Jan-Markus
2013-01-01
Tutorium quantum mechanics is a book, written by an experiences tutor for all, who finally want to understand from the beginning physics and mathematics of quantum mechanics. The book treats the matter of the corresponding course in the framework of theoretical physics. The main topic lies in this book on the general postulates of quantum mechanics and the clarification of the fundamental terms. What is precisely a Hilbert space? What is an Hermitian operator? A tensor product? An entangled state? To what extend wave functions are vectors? The postulates raise until today also many questions concerning their interpretation. This is discussed in a separate chapter. This book is structured in such a way that each step and each new term is explained by means of simple examples. The author attaches great importance to the clarity of the applied mathematics - something, what he and many students in other textbooks had hitherto to miss. By this main topic is also very well suited for mathematicists, who want to deal with the issue. In the examination preparation the book is especially well suited for the clarification of terms and questions of understanding. The questions of understanding and the exercise problems interspersed in the text with solutions support additionally the learning and the preparation for examination.
I, Quantum Robot: Quantum Mind control on a Quantum Computer
Zizzi, Paola
2008-01-01
The logic which describes quantum robots is not orthodox quantum logic, but a deductive calculus which reproduces the quantum tasks (computational processes, and actions) taking into account quantum superposition and quantum entanglement. A way toward the realization of intelligent quantum robots is to adopt a quantum metalanguage to control quantum robots. A physical implementation of a quantum metalanguage might be the use of coherent states in brain signals.
Physics. Pt. 2. Atomic, molecular, and quantum physics - experimental and theoretical foundations
International Nuclear Information System (INIS)
Weber, R.
2007-01-01
The experimental and theoretical foundations of physics are mediated in this course in integrated representation. Many exercise problems deepen the understanding and help directedly in the preparation of clausures and examinations. The pictures are always in two colours. The present volume contains all themes of modern physics
The quantum rules how the laws of physics explain love, success, and everyday life
Das, Kunal K
2015-01-01
A New York Times Best Seller! Here is a book to lead you through the fascinating intersections of life and physics with humor and intelligence. Find out how the laws of physics define every aspect of our lives and society, from human nature and relationships to geopolitical issues like financial markets, globalization and immigration. The Quantum Rules is a different kind of physics book, as easy to read as a novel and directly relevant for everyday life issues that affect us all. It is not meant to dazzle you with unproven speculations that have no bearing on your life. Rather, The Quantum Rules will familiarize you with the important and established laws at the heart of physics, in a way never done before by showing how the defining patterns of our lives, our behavior and our society already follow similar rules. Never took an interest in science before? No problem! you will still understand everything and find plenty to relate to. A scientist or a science junkie? You will find a different perspective on...
Crossover physics in the nonequilibrium dynamics of quenched quantum impurity systems.
Vasseur, Romain; Trinh, Kien; Haas, Stephan; Saleur, Hubert
2013-06-14
A general framework is proposed to tackle analytically local quantum quenches in integrable impurity systems, combining a mapping onto a boundary problem with the form factor approach to boundary-condition-changing operators introduced by Lesage and Saleur [Phys. Rev. Lett. 80, 4370 (1998)]. We discuss how to compute exactly the following two central quantities of interest: the Loschmidt echo and the distribution of the work done during the quantum quench. Our results display an interesting crossover physics characterized by the energy scale T(b) of the impurity corresponding to the Kondo temperature. We discuss in detail the noninteracting case as a paradigm and benchmark for more complicated integrable impurity models and check our results using numerical methods.
Snyder, D
2002-01-01
A straightforward explanation of fundamental tenets of quantum mechanics concerning the wave function results in the thesis that the quantum mechanical wave function is a link between human cognition and the physical world. The reticence on the part of physicists to adopt this thesis is discussed. A comparison is made to the behaviorists' consideration of mind, and the historical roots of how the problem concerning the quantum mechanical wave function arose are discussed. The basis for an empirical demonstration that the wave function is a link between human cognition and the physical world is provided through developing an experiment using methodology from psychology and physics. Based on research in psychology and physics that relied on this methodology, it is likely that Einstein, Podolsky, and Rosen's theoretical result that mutually exclusive wave functions can simultaneously apply to the same concrete physical circumstances can be implemented on an empirical level.
Principle of minimum distance in space of states as new principle in quantum physics
International Nuclear Information System (INIS)
Ion, D. B.; Ion, M. L. D.
2007-01-01
The mathematician Leonhard Euler (1707-1783) appears to have been a philosophical optimist having written: 'Since the fabric of universe is the most perfect and is the work of the most wise Creator, nothing whatsoever take place in this universe in which some relation of maximum or minimum does not appear. Wherefore, there is absolutely no doubt that every effect in universe can be explained as satisfactory from final causes themselves the aid of the method of Maxima and Minima, as can from the effective causes'. Having in mind this kind of optimism in the papers mentioned in this work we introduced and investigated the possibility to construct a predictive analytic theory of the elementary particle interaction based on the principle of minimum distance in the space of quantum states (PMD-SQS). So, choosing the partial transition amplitudes as the system variational variables and the distance in the space of the quantum states as a measure of the system effectiveness, we obtained the results presented in this paper. These results proved that the principle of minimum distance in space of quantum states (PMD-SQS) can be chosen as variational principle by which we can find the analytic expressions of the partial transition amplitudes. In this paper we present a description of hadron-hadron scattering via principle of minimum distance PMD-SQS when the distance in space of states is minimized with two directional constraints: dσ/dΩ(±1) = fixed. Then by using the available experimental (pion-nucleon and kaon-nucleon) phase shifts we obtained not only consistent experimental tests of the PMD-SQS optimality, but also strong experimental evidences for new principles in hadronic physics such as: Principle of nonextensivity conjugation via the Riesz-Thorin relation (1/2p + 1/2q = 1) and a new Principle of limited uncertainty in nonextensive quantum physics. The strong experimental evidence obtained here for the nonextensive statistical behavior of the [J, θ]-quantum
PREFACE: 6th International Workshop on Pseudo-Hermitian Hamiltonians in Quantum Physics
Fring, Andreas; Jones, Hugh; Znojil, Miloslav
2008-06-01
Attempts to understand the quantum mechanics of non-Hermitian Hamiltonian systems can be traced back to the early days, one example being Heisenberg's endeavour to formulate a consistent model involving an indefinite metric. Over the years non-Hermitian Hamiltonians whose spectra were believed to be real have appeared from time to time in the literature, for instance in the study of strong interactions at high energies via Regge models, in condensed matter physics in the context of the XXZ-spin chain, in interacting boson models in nuclear physics, in integrable quantum field theories as Toda field theories with complex coupling constants, and also very recently in a field theoretical scenario in the quantization procedure of strings on an AdS5 x S5 background. Concrete experimental realizations of these types of systems in the form of optical lattices have been proposed in 2007. In the area of mathematical physics similar non-systematic results appeared sporadically over the years. However, intensive and more systematic investigation of these types of non- Hermitian Hamiltonians with real eigenvalue spectra only began about ten years ago, when the surprising discovery was made that a large class of one-particle systems perturbed by a simple non-Hermitian potential term possesses a real energy spectrum. Since then regular international workshops devoted to this theme have taken place. This special issue is centred around the 6th International Workshop on Pseudo-Hermitian Hamiltonians in Quantum Physics held in July 2007 at City University London. All the contributions contain significant new results or alternatively provide a survey of the state of the art of the subject or a critical assessment of the present understanding of the topic and a discussion of open problems. Original contributions from non-participants were also invited. Meanwhile many interesting results have been obtained and consensus has been reached on various central conceptual issues in the
Scarani, Valerio
1998-01-01
The aim of this thesis was to explain what quantum computing is. The information for the thesis was gathered from books, scientific publications, and news articles. The analysis of the information revealed that quantum computing can be broken down to three areas: theories behind quantum computing explaining the structure of a quantum computer, known quantum algorithms, and the actual physical realizations of a quantum computer. The thesis reveals that moving from classical memor...
The limits of predictability: Indeterminism and undecidability in classical and quantum physics
Korolev, Alexandre V.
This thesis is a collection of three case studies, investigating various sources of indeterminism and undecidability as they bear upon in principle unpredictability of the behaviour of mechanistic systems in both classical and quantum physics. I begin by examining the sources of indeterminism and acausality in classical physics. Here I discuss the physical significance of an often overlooked and yet important Lipschitz condition, the violation of which underlies the existence of anomalous non-trivial solutions in the Norton-type indeterministic systems. I argue that the singularity arising from the violation of the Lipschitz condition in the systems considered appears to be so fragile as to be easily destroyed by slightly relaxing certain (infinite) idealizations required by these models. In particular, I show that the idealization of an absolutely nondeformable, or infinitely rigid, dome appears to be an essential assumption for anomalous motion to begin; any slightest elastic deformations of the dome due to finite rigidity of the dome destroy the shape of the dome required for indeterminism to obtain. I also consider several modifications of the original Norton's example and show that indeterminism in these cases, too, critically depends on the nature of certain idealizations pertaining to elastic properties of the bodies in these models. As a result, I argue that indeterminism of the Norton-type Lipschitz-indeterministic systems should rather be viewed as an artefact of certain (infinite) idealizations essential for the models, depriving the examples of much of their intended metaphysical import, as, for example, in Norton's antifundamentalist programme. Second, I examine the predictive computational limitations of a classical Laplace's demon. I demonstrate that in situations of self-fulfilling prognoses the class of undecidable propositions about certain future events, in general, is not empty; any Laplace's demon having all the information about the world now
Human Perception of Physical Experiments and the Simplex Interpretation of Quantum Physics
Directory of Open Access Journals (Sweden)
Isaeva E. A.
2008-01-01
Full Text Available In this paper it is argued that knowledge dividing the usual, unusual, transient and transcendental depends on human perception of the world (macro or micro and depends too on the inclusion of human consciousness in the system. For the analysis of this problem the idea of "Schrodinger’s cat" is employed. Transient and transcendental knowledge of the state of Schrodinger’s cat corresponds to the case when the observer’s consciousness is included in the system. Here it is possible to speak about the latent parameters of the sub quantum world of which Einstein was convinced. Knowledge of the unusual state of Schrodinger’s cat, simultaneously alive and dead, corresponds to a case of the open micro world. The usual knowledge of the state of Schrodinger’s cat (alive or dead corresponds to a case of the open macrocosm. Each world separately divides the objective and illusory.
Quantum Distinction: Quantum Distinctiones!
Zeps, Dainis
2009-01-01
10 pages; How many distinctions, in Latin, quantum distinctiones. We suggest approach of anthropic principle based on anthropic reference system which should be applied equally both in theoretical physics and in mathematics. We come to principle that within reference system of life subject of mathematics (that of thinking) should be equated with subject of physics (that of nature). For this reason we enter notions of series of distinctions, quantum distinction, and argue that quantum distinct...
Héraud, Jean-Loup; Lautesse, Philippe; Ferlin, Fabrice; Chabot, Hugues
2017-05-01
Our work extends a previous study of epistemological presuppositions in teaching quantum physics in upper scientific secondary school in France. Here, the problematic reference of quantum theory's concepts is treated at the ontological level (the counterintuitive nature of quantum objects). We consider the approach of using narratives describing possible alternative worlds to address the issue. These possible worlds are based on the counterfactual logic developed in the work of D. Lewis. We will show that the narratives written by G. Gamow describe such possible worlds. Some parts of these narratives are found in textbooks in France. These worlds are governed by laws similar to but importantly different from those in our real world. They allow us to materialize properties inaccessible to everyday experience. In this sense, these fiction stories make ontological propositions concerning the nature and structure of the fundamental elements of our physical universe.
Logical foundations of the Jauch-Piron approach to quantum physics
International Nuclear Information System (INIS)
Cattaneo, G.; Pozza, C.D.; Garola, C.; Nistico, G.
1988-01-01
We make a critical analysis of the basic concepts of the Jauch-Piron (JP) approach to quantum physics. Then, we exhibit a formalized presentation of the mathematical structure of the JP theory by introducing it as a completely formalized syntactic system, i.e., we construct a formalized language L/sub e/ and formally state the logical-deductive structure of the JP theory by means of L/sub e/. Finally, we show that the JP syntactic system can be endowed with an intended interpretation, which yields a physical model of the system. A mathematical model endowed with a physical interpretation is given which establishes (in the usual sense of the model theory) the coherence of the JP syntactic system
On the Logical Foundations of the Jauch-Piron Approach to Quantum Physics
Cattaneo, Gianpiero; Pozza, Carlo Dalla; Garola, Claudio; Nisticò, Giuseppe
1988-11-01
We make a critical analysis of the basic concepts of the Jauch-Piron (JP) approach to quantum physics. Then, we exhibit a formalized presentation of the mathematical structure of the JP theory by introducing it as a completely formalized syntactic system, i.e., we construct a formalized language L e and formally state the logical-deductive structure of the JP theory by means of L e . Finally, we show that the JP syntactic system can be endowed with an intended interpretation, which yields a physical model of the system. A mathematical model endowed with a physical interpretation is given which establishes (in the usual sense of the model theory) the coherence of the JP syntactic system.
A review of progress in the physics of open quantum systems: theory and experiment.
Rotter, I; Bird, J P
2015-11-01
This report on progress explores recent advances in our theoretical and experimental understanding of the physics of open quantum systems (OQSs). The study of such systems represents a core problem in modern physics that has evolved to assume an unprecedented interdisciplinary character. OQSs consist of some localized, microscopic, region that is coupled to an external environment by means of an appropriate interaction. Examples of such systems may be found in numerous areas of physics, including atomic and nuclear physics, photonics, biophysics, and mesoscopic physics. It is the latter area that provides the main focus of this review, an emphasis that is driven by the capacity that exists to subject mesoscopic devices to unprecedented control. We thus provide a detailed discussion of the behavior of mesoscopic devices (and other OQSs) in terms of the projection-operator formalism, according to which the system under study is considered to be comprised of a localized region (Q), embedded into a well-defined environment (P) of scattering wavefunctions (with Q + P = 1). The Q subspace must be treated using the concepts of non-Hermitian physics, and of particular interest here is: the capacity of the environment to mediate a coupling between the different states of Q; the role played by the presence of exceptional points (EPs) in the spectra of OQSs; the influence of EPs on the rigidity of the wavefunction phases, and; the ability of EPs to initiate a dynamical phase transition (DPT). EPs are singular points in the continuum, at which two resonance states coalesce, that is where they exhibit a non-avoided crossing. DPTs occur when the quantum dynamics of the open system causes transitions between non-analytically connected states, as a function of some external control parameter. Much like conventional phase transitions, the behavior of the system on one side of the DPT does not serve as a reliable indicator of that on the other. In
Bays, Harold
2005-05-01
Excessive fat (adiposity) and dysfunctional fat (adiposopathy) constitute the most common worldwide epidemics of our time -- and perhaps of all time. Ongoing efforts to explain how the micro (adipocyte) and macro (body organ) biologic systems interact through function and dysfunction in promoting Type 2 diabetes mellitus, hypertension and dyslipidemia are not unlike the mechanistic and philosophical thinking processes involved in reconciling the micro (quantum physics) and macro (general relativity) theories in physics. Currently, the term metabolic syndrome refers to a constellation of consequences often associated with excess body fat and is an attempt to unify the associations known to exist between the four fundamental metabolic diseases of obesity, hyperglycemia (including Type 2 diabetes mellitus), hypertension and dyslipidemia. However, the association of adiposity with these metabolic disorders is not absolute and the metabolic syndrome does not describe underlying causality, nor does the metabolic syndrome necessarily reflect any reasonably related pathophysiologic process. Just as with quantum physics, general relativity and the four fundamental forces of the universe, the lack of an adequate unifying theory of micro causality and macro consequence is unsatisfying, and in medicine, impairs the development of agents that may globally improve both obesity and obesity-related metabolic disease. Emerging scientific and clinical evidence strongly supports the novel concept that it is not adiposity alone, but rather it is adiposopathy that is the underlying cause of most cases of Type 2 diabetes mellitus, hypertension and dyslipidemia. Adiposopathy is a plausible Theory of Everything for mankind's greatest metabolic epidemics.
A study on pre-service physics teachers' conceptualization on elementary quantum mechanics
Directory of Open Access Journals (Sweden)
Glauco Cohen Ferreira Pantoja
2017-08-01
Full Text Available In this work, we present the results of a research in which we aimed to evidence obstacles and advances in pre-service teachers’ conceptualization on a subject involving elementary Quantum Mechanics. We based our analysis on the theories due to David Ausubel and Gèrard Vergnaud to study Meaningful Learning patterns, both in predicative and operatory form of knowledge, of six students involved in a didactical intervention composed of six classes, in which we emphasized both similarities and differences between Classical and Quantum Physics. With this intervention, we intended to teach the concepts of Physical System, Dynamical Variables, State of a Physical System and Time Evolution. We guided our data analysis by the methodology of content analysis (Bardin, 2008 and it turned possible to map Meaningful Learning patterns involving the four concepts to which were associated a set of essential features (in the predicative stage and a set of theorems-in-action (in the operatory stage relating the aim-concepts in problem-solving or conceptual mapping.
Boscarino, Giuseppe
2006-06-01
It is questioned: Is quantum mechanics a new science or a new (or rather old) philosophy of physical science? It is shown that Einstein's attempt in his article of 1935 to bring the concept of "element" from the classical (we call it Italic) philosophical-epistemological tradition, which goes under the names of Pythagoras Parmenides, Democritus, and Newton, into quantum mechanical theory is unclear, inadequate and contradictory.
Physical nonexistence of signals going backwards in time, and quantum mechanics
Energy Technology Data Exchange (ETDEWEB)
Garuccio, A. (Bari Univ. (Italy). Ist. di Fisica; Istituto Nazionale di Fisica Nucleare, Bari (Italy)); Maccarrone, G.D. (Catania Univ. (Italy). Scuola di Specializzazione in Fisica); Recami, E. (Catania Univ. (Italy). Ist. di Fisica; Istituto Nazionale di Fisica Nucleare, Catania (Italy); Centro Siciliano di Fisica Nucleare e Struttura della Materia, Catania (Italy))
1980-01-12
With regard to the recent results of new experiments about the EPR-paradox, which seem to disagree with Bell inequality and appear to confirm quantum mechanics, some theoretical interpretations have been proposed. In this letter, it is shown that the interpretations invoking transmission of signals into the past do not seem to be physically acceptable. The positive role of the ''Reinterpretation Principle'' (for an orthodox reinterpretation of the ''advanced solutions'') is in particular stressed.
Quantum tomography for collider physics. Illustrations with lepton-pair production
Energy Technology Data Exchange (ETDEWEB)
Martens, John C.; Ralston, John P.; Takaki, J.D.T. [The University of Kansas, Department of Physics and Astronomy, Lawrence, KS (United States)
2018-01-15
Quantum tomography is a method to experimentally extract all that is observable about a quantum mechanical system. We introduce quantum tomography to collider physics with the illustration of the angular distribution of lepton pairs. The tomographic method bypasses much of the field-theoretic formalism to concentrate on what can be observed with experimental data. We provide a practical, experimentally driven guide to model-independent analysis using density matrices at every step. Comparison with traditional methods of analyzing angular correlations of inclusive reactions finds many advantages in the tomographic method, which include manifest Lorentz covariance, direct incorporation of positivity constraints, exhaustively complete polarization information, and new invariants free from frame conventions. For example, experimental data can determine the entanglement entropy of the production process. We give reproducible numerical examples and provide a supplemental standalone computer code that implements the procedure. We also highlight a property of complex positivity that guarantees in a least-squares type fit that a local minimum of a χ{sup 2} statistic will be a global minimum: There are no isolated local minima. This property with an automated implementation of positivity promises to mitigate issues relating to multiple minima and convention dependence that have been problematic in previous work on angular distributions. (orig.)
Retrocausation in quantum mechanics and the effects of minds on the creation of physical reality
Stapp, Henry P.
2017-05-01
The classical physical theories that prevailed in science from the time of Isaac Newton until the dawn of the twentieth century were empirically based on human experience and made predictions about our mental experiences, yet excluded from the dynamics all mental properties. But how can one rationally get mental things out if no mental elements are put in? The key step in the creation of quantum mechanics during 1925 by Heisenberg and his colleagues was to recognize and emphasize the essential dynamical role of mental properties in the creation of our mental empirical findings. This basic feature of quantum mechanics was cast into rigorous mathematical form by John von Neumann, and was made a central feature of contemporary relativistic quantum field theory by the work of Tomonaga and Schwinger. That theory is causally strictly forward in time. But it is explained here how it can nevertheless accommodate the seeming backward-in-time causal effects reported by D.J. Bem, and many others, by means of a slight biasing of the famous Born Rule. The purpose of this communication is to explain how those reported retrocausal findings can be explained by a strictly forward-in-time and nearly orthodox causal dynamics that, however, permits the Born Rule to be slightly biased under certain conditions. A feasible experiment is proposed that, if it gives the outcomes predicted by the proposed theory, will provide evidence in favor of this causally forward-in-time and nearly orthodox explanation of the reported retrocausal effects.
Quantum tomography for collider physics: illustrations with lepton-pair production
Martens, John C.; Ralston, John P.; Takaki, J. D. Tapia
2018-01-01
Quantum tomography is a method to experimentally extract all that is observable about a quantum mechanical system. We introduce quantum tomography to collider physics with the illustration of the angular distribution of lepton pairs. The tomographic method bypasses much of the field-theoretic formalism to concentrate on what can be observed with experimental data. We provide a practical, experimentally driven guide to model-independent analysis using density matrices at every step. Comparison with traditional methods of analyzing angular correlations of inclusive reactions finds many advantages in the tomographic method, which include manifest Lorentz covariance, direct incorporation of positivity constraints, exhaustively complete polarization information, and new invariants free from frame conventions. For example, experimental data can determine the entanglement entropy of the production process. We give reproducible numerical examples and provide a supplemental standalone computer code that implements the procedure. We also highlight a property of complex positivity that guarantees in a least-squares type fit that a local minimum of a χ 2 statistic will be a global minimum: There are no isolated local minima. This property with an automated implementation of positivity promises to mitigate issues relating to multiple minima and convention dependence that have been problematic in previous work on angular distributions.
O Some Aspects of the Relationship Between Quantum Physics, Gravity and Thermodynamics.
Stephens, Christopher Rhodes
In this dissertation an attempt is made to shed some new light on various aspects of the relation between quantum physics, gravity and thermodynamics. The well known Hawking-Unruh effect is explored and reviewed and some original results found. It is found that the noise spectrum for a massless scalar field along an accelerated trajectory in odd dimensional Minkowski space has a (pseudo) -Fermi-Dirac form contrary to expectations. Ambiguous questions about covariance that have arisen when considering the physics of accelerated observers are addressed critically. It is found that if one is careful about specifying just what "observer" means then no ambiguities can arise. The idea of what constitutes a "particle" is also critically discussed. The uniqueness of the gravitational field vis a vis thermal effects is investigated. It is found that pair production in a uniform electric field admits of a thermal interpretation, (one with some interesting subtleties), thereby showing the non-uniqueness of gravity in this respect. The notion of intrinsic entropy remains a singular feature of gravity however. A corollary of the above is that the Unruh effect is an integral part of a quantum field theory and not some additional baggage. In treating the above questions some very interesting techniques are developed. The PTPI formalism allows a relativistic quantum field calculation to be performed without ever mentioning a quantum field(!) by reformulating such a problem into a quantum mechanical analog. As the problem is now finite dimensional, one loop determinants can be calculated using the method of Jacobi fields, rather than as infinite dimensional functional determinants. In general the methodology allows one to obtain covariances of partial differential equations from the covariances of ordinary differential equations!. The thermal effects discussed herein are seen to be just a small part of a much broader phenomenon--finite size effects. Such effects have been
Proceedings of quantum field theory, quantum mechanics, and quantum optics
International Nuclear Information System (INIS)
Dodonov, V.V.; Man; ko, V.I.
1991-01-01
This book contains papers presented at the XVIII International Colloquium on Group Theoretical Methods in Physics held in Moscow on June 4-9, 1990. Topics covered include; applications of algebraic methods in quantum field theory, quantum mechanics, quantum optics, spectrum generating groups, quantum algebras, symmetries of equations, quantum physics, coherent states, group representations and space groups
Energy Technology Data Exchange (ETDEWEB)
Belloni, M., E-mail: mabelloni@davidson.edu [Physics Department, Davidson College, Davidson, NC 28035 (United States); Robinett, R.W., E-mail: rick@phys.psu.edu [Department of Physics, The Pennsylvania State University, University Park, PA 16802 (United States)
2014-07-01
The infinite square well and the attractive Dirac delta function potentials are arguably two of the most widely used models of one-dimensional bound-state systems in quantum mechanics. These models frequently appear in the research literature and are staples in the teaching of quantum theory on all levels. We review the history, mathematical properties, and visualization of these models, their many variations, and their applications to physical systems.
Energy Technology Data Exchange (ETDEWEB)
Dattoli, Giuseppe; Torre, Amalia [ENEA, Centro Ricerche Frascati, Rome (Italy). Dipt. Innovazione; Ottaviani, Pier Luigi [ENEA, Centro Ricerche Bologna (Italy); Vasquez, Luis [Madris, Univ. Complutense (Spain). Dept. de Matemateca Aplicado
1997-10-01
The finite-difference based integration method for evolution-line equations is discussed in detail and framed within the general context of the evolution operator picture. Exact analytical methods are described to solve evolution-like equations in a quite general physical context. The numerical technique based on the factorization formulae of exponential operator is then illustrated and applied to the evolution-operator in both classical and quantum framework. Finally, the general view to the finite differencing schemes is provided, displaying the wide range of applications from the classical Newton equation of motion to the quantum field theory.
Directory of Open Access Journals (Sweden)
Ihor V. Korsun
2017-10-01
Full Text Available The aim of this article is to prove the advisability of using the e-learning of quantum physics in the Moodle environment to help students achieve better success in this difficult subject area. The possibilities of Moodle in a distance learning environment have been analysed. E-learning tool of quantum physics in the Moodle environment has been described, and its educational opportunities have been determined. The need for material models and thought models for teaching of quantum physics has been proven. Modeling method and thought experiments explain phenomena of physics help to better understand real experiments and the essence of physics theories. The method of creation of computer models using Easy Gif Animator has been discussed. The requirements for material models have been identified, and an example of material model of Large Hadron Collider has been demonstrated. Results showed that e-learning of quantum physics increases the level of students' cognitive activity. This technique can be used for teaching other sections of physics and other natural sciences.
Infinite potential: what quantum physics reveals about how we should live
Schafer, Lothar
2013-01-01
A hopeful and controversial view of the universe and ourselves based on the principles of quantum physics, offering a way of making our lives and the world better, with a foreword by Deepak Chopra In Infinite Potential, physical chemist Lothar Schäfer presents a stunning view of the universe as interconnected, nonmaterial, composed of a field of infinite potential, and conscious. With his own research as well as that of some of the most distinguished scientists of our time, Schäfer moves us from a reality of Darwinian competition to cooperation, a meaningless universe to a meaningful one, and a disconnected, isolated existence to an interconnected one. In so doing, he shows us that our potential is infinite and calls us to live in accordance with the order of the universe, creating a society based on the cosmic principle of connection, emphasizing cooperation and community.
12th DESY Workshop on Elementary Particle Physics: Loops and Legs in Quantum Field Theory
LL2014
2014-01-01
The bi-annual international conference “Loops and Legs in Quantum Field Theory” has been held at Weimar, Germany, from April 27 to May 02, 2014. It has been the 12th conference of this series, started in 1992. The main focus of the conference are precision calculations of multi- loop and multi-leg processes in elementary particle physics for processes at present and future high-energy facilities within and beyond the Standard Model. At present many physics questions studied deal with processes at the LHC and future facilities like the ILC. A growing number of contributions deals with important developments in the field of computational technologies and algorithmic methods, including large-scale computer algebra, efficient methods to compute large numbers of Feynman diagrams, analytic summation and integration methods of various kinds, new related function spaces, precise numerical methods and Monte Carlo simulations. The present conference has been attended by more than 110 participants from all over the ...
Classical solutions in quantum field theory solitons and instantons in high energy physics
Weinberg, Erick J
2012-01-01
Classical solutions play an important role in quantum field theory, high energy physics and cosmology. Real-time soliton solutions give rise to particles, such as magnetic monopoles, and extended structures, such as domain walls and cosmic strings, that have implications for early universe cosmology. Imaginary-time Euclidean instantons are responsible for important nonperturbative effects, while Euclidean bounce solutions govern transitions between metastable states. Written for advanced graduate students and researchers in elementary particle physics, cosmology and related fields, this book brings the reader up to the level of current research in the field. The first half of the book discusses the most important classes of solitons: kinks, vortices and magnetic monopoles. The cosmological and observational constraints on these are covered, as are more formal aspects, including BPS solitons and their connection with supersymmetry. The second half is devoted to Euclidean solutions, with particular emphasis on ...
Physical microscopic free-choice model in the framework of a Darwinian approach to quantum mechanics
Energy Technology Data Exchange (ETDEWEB)
Baladron, Carlos [Departamento de Fisica Teorica, Atomica y Optica, Universidad de Valladolid, E-47011, Valladolid (Spain)
2017-06-15
A compatibilistic model of free choice for a fundamental particle is built within a general framework that explores the possibility that quantum mechanics be the emergent result of generalised Darwinian evolution acting on the abstract landscape of possible physical theories. The central element in this approach is a probabilistic classical Turing machine -basically an information processor plus a randomiser- methodologically associated with every fundamental particle. In this scheme every system acts not under a general law, but as a consequence of the command of a particular, evolved algorithm. This evolved programme enables the particle to algorithmically anticipate possible future world configurations in information space, and as a consequence, without altering the natural forward causal order in physical space, to incorporate elements to the decision making procedure that are neither purely random nor strictly in the past, but in a possible future. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Chandrasekhar limit: an elementary approach based on classical physics and quantum theory
Pinochet, Jorge; Van Sint Jan, Michael
2016-05-01
In a brief article published in 1931, Subrahmanyan Chandrasekhar made public an important astronomical discovery. In his article, the then young Indian astrophysicist introduced what is now known as the Chandrasekhar limit. This limit establishes the maximum mass of a stellar remnant beyond which the repulsion force between electrons due to the exclusion principle can no longer stop the gravitational collapse. In the present article, we create an elemental approximation to the Chandrasekhar limit, accessible to non-graduate science and engineering students. The article focuses especially on clarifying the origins of Chandrasekhar’s discovery and the underlying physical concepts. Throughout the article, only basic algebra is used as well as some general notions of classical physics and quantum theory.
A course in mathematical physics 3 quantum mechanics of atoms and molecules
Thirring, Walter
1981-01-01
In this third volume of A Course in Mathematical Physics I have attempted not simply to introduce axioms and derive quantum mechanics from them, but also to progress to relevant applications. Reading the axiomatic litera ture often gives one the impression that it largely consists of making refined axioms, thereby freeing physics from any trace of down-to-earth residue and cutting it off from simpler ways of thinking. The goal pursued here, however, is to come up with concrete results that can be compared with experimental facts. Everything else should be regarded only as a side issue, and has been chosen for pragmatic reasons. It is precisely with this in mind that I feel it appropriate to draw upon the most modern mathematical methods. Only by their means can the logical fabric of quantum theory be woven with a smooth structure; in their absence, rough spots would . inevitably appear, especially in the theory of unbounded operators, where the details are too intricate to be comprehended easily. Great care...
Bryce, Richard A
2011-04-01
The ability to accurately predict the interaction of a ligand with its receptor is a key limitation in computer-aided drug design approaches such as virtual screening and de novo design. In this article, we examine current strategies for a physics-based approach to scoring of protein-ligand affinity, as well as outlining recent developments in force fields and quantum chemical techniques. We also consider advances in the development and application of simulation-based free energy methods to study protein-ligand interactions. Fuelled by recent advances in computational algorithms and hardware, there is the opportunity for increased integration of physics-based scoring approaches at earlier stages in computationally guided drug discovery. Specifically, we envisage increased use of implicit solvent models and simulation-based scoring methods as tools for computing the affinities of large virtual ligand libraries. Approaches based on end point simulations and reference potentials allow the application of more advanced potential energy functions to prediction of protein-ligand binding affinities. Comprehensive evaluation of polarizable force fields and quantum mechanical (QM)/molecular mechanical and QM methods in scoring of protein-ligand interactions is required, particularly in their ability to address challenging targets such as metalloproteins and other proteins that make highly polar interactions. Finally, we anticipate increasingly quantitative free energy perturbation and thermodynamic integration methods that are practical for optimization of hits obtained from screened ligand libraries.
Complexity in quantum field theory and physics beyond the standard model
International Nuclear Information System (INIS)
Goldfain, Ervin
2006-01-01
Complex quantum field theory (abbreviated c-QFT) is introduced in this paper as an alternative framework for the description of physics beyond the energy range of the standard model. The mathematics of c-QFT is based on fractal differential operators that generalize the momentum operators of conventional quantum field theory (QFT). The underlying premise of our approach is that c-QFT contains the right analytical tools for dealing with the asymptotic regime of QFT. Canonical quantization of c-QFT leads to the following findings: (i) the Fock space of c-QFT includes fractional numbers of particles and antiparticles per state (ii) c-QFT represents a generalization of topological field theory and (iii) classical limit of c-QFT is equivalent to field theory in curved space-time. The first finding provides a field-theoretic motivation for the transfinite discretization approach of El-Naschie's ε (∞) theory. The second and third findings suggest the dynamic unification of boson and fermion fields as particles with fractional spin, as well as the close connection between spin and space-time topology beyond the conventional physics of the standard model
Complexity in quantum field theory and physics beyond the standard model
Energy Technology Data Exchange (ETDEWEB)
Goldfain, Ervin [OptiSolve Consulting, 4422 Cleveland Road, Syracuse, NY 13215 (United States)
2006-05-15
Complex quantum field theory (abbreviated c-QFT) is introduced in this paper as an alternative framework for the description of physics beyond the energy range of the standard model. The mathematics of c-QFT is based on fractal differential operators that generalize the momentum operators of conventional quantum field theory (QFT). The underlying premise of our approach is that c-QFT contains the right analytical tools for dealing with the asymptotic regime of QFT. Canonical quantization of c-QFT leads to the following findings: (i) the Fock space of c-QFT includes fractional numbers of particles and antiparticles per state (ii) c-QFT represents a generalization of topological field theory and (iii) classical limit of c-QFT is equivalent to field theory in curved space-time. The first finding provides a field-theoretic motivation for the transfinite discretization approach of El-Naschie's {epsilon} {sup ({infinity}}{sup )} theory. The second and third findings suggest the dynamic unification of boson and fermion fields as particles with fractional spin, as well as the close connection between spin and space-time topology beyond the conventional physics of the standard model.
Searching for new physics at the frontiers with lattice quantum chromodynamics.
Van de Water, Ruth S
2012-07-01
Numerical lattice-quantum chromodynamics (QCD) simulations, when combined with experimental measurements, allow the determination of fundamental parameters of the particle-physics Standard Model and enable searches for physics beyond-the-Standard Model. We present the current status of lattice-QCD weak matrix element calculations needed to obtain the elements and phase of the Cabibbo-Kobayashi-Maskawa (CKM) matrix and to test the Standard Model in the quark-flavor sector. We then discuss evidence that may hint at the presence of new physics beyond the Standard Model CKM framework. Finally, we discuss two opportunities where we expect lattice QCD to play a pivotal role in searching for, and possibly discovery of, new physics at upcoming high-intensity experiments: rare decays and the muon anomalous magnetic moment. The next several years may witness the discovery of new elementary particles at the Large Hadron Collider (LHC). The interplay between lattice QCD, high-energy experiments at the LHC, and high-intensity experiments will be needed to determine the underlying structure of whatever physics beyond-the-Standard Model is realized in nature. © 2012 New York Academy of Sciences.
Energy Technology Data Exchange (ETDEWEB)
Huebel, Horst
2010-07-01
Traditionally in the center of interest on quantum physics referring to schools the question lies, whether electrons and photons are now particles or waves, a question, which is often characterized by the phrase ''wave-particle dualism'', which notoriously not exists in its original meaning. Against that by the author - basing on important preparatory works of Kueblbeck and Mueller - a new concept for the treatment of quantum physics for the school was proposed, which puts ''basic facts'' in the foreground, comparable with the Kueblbeck-Mueller ''characteristic features''. The ''basic facts'' are similar to axioms of quantum physics, by means of which a large number of experiments and phenomena can be ''explained'' at least qualitatively - in a heuristic way -. Instead of the so-called ''wave-particle dualism'' here uncertainty and complementarity are put in the foreground. The new concept is in the Internet under http://www.forphys.de extensively presented with many further materials. In the partial volumes of this publication manifold and carefully elaborated teaching materials are presented, by means of which scholars can get themselves the partial set of quantum physics referring to schools by different methods like learn at stations, short referates, Internet research, group puzzle, the query-sheet or the card-index method etc. In the present 2. part materials for the ''basic facts'' of quantum physics are prepared, by which also modern experiments can be interpreted. Here deals it with the getting of knowledge and application of the ''basic Facts''. This pursues also by real scholar experiments, simulations and analogy tests. The scholars obtain so more simply than generally a deeper insight in quantum physics.
Rechberger, Elke Ruth
1999-11-01
Prior to the 1600s c.e., the church was the final authority for theories about the universe and humanity's role within it. However, when the mathematical theories put forth by scientists such as Copernicus and Galileo refuted traditional theological explanations about the cosmos, a shift to science as the premiere authority for theories was established, a tradition which continues to this day. In the following century, the work of Newton set forth a theory of the universe operating as a machine, where all things were potentially knowable, measurable, and predictable. His mechanistic hypotheses helped substantiate a corollary philosophy known as modernism. In the early 1900s, Einstein's theories about light and relativity began to indicate a universe significantly less absolute. His work set the stage for the development of quantum physics theories, whose hallmarks are probability, uncertainty, and complementarity. Quantum physics theories helped substantiate the philosophy known as postmodernism, where truth is nonexistent, reality is a subjectively constructed phenomenon, and the concept of an individual self is considered an illusion. Given that developments in physics have had profound impact across academic disciplines, including psychology, this study examine the effect of major revolutions in physics to corollary developments in theories about the self in psychology. It is the assertion of this work that modernist conceptualization of the self is one that is highly individualistic and defined in mechanistic terms, whereas the postmodern conceptualization of the self is significantly more socially constructed and has more interpersonally fluid, amorphous boundaries. Implications for conceptualizations of the self from either the modern or postmodern paradigm are discussed, as well as suggestions for future theory development.
Directory of Open Access Journals (Sweden)
Aguinaldo Robinson de Souza
2016-12-01
Full Text Available In this paper we present a fable, scientific and metaphorical analysis of the book Alice in Quantumland: An Allegory of Quantum Physics. The objective is to present, through the analysis, subsidies that address the teacher of high schools, how a paradidactic book can be used in the classroom for teaching concepts of quantum physics. The issue, though complex, is likely to be developed in an analogical and metaphorical perspective, in the fable, scientific, temporal and spatial level. The paradidactic book should be considered as a support material to the textbook complementing the activities that allow the development of the understanding of concepts not covered in a common sense approach.
BOOK REVIEW: Quantum Generations. A history of physics in the twentieth century
Brown, Neil
2000-03-01
Physics has a long history, but more physics has been discovered in the twentieth century than in all previous eras together. That in itself would be a sufficient justification for a history of physics in the twentieth century, but the end of the previous century also marked a discontinuity, from Newtonian classical physics to relativity and quantum mechanics. If any single event marks the start of the process it is the discovery of x-rays in 1895, and Kragh's century spans from about 1895 to about 1995. It is, of course, too much for a single volume, even a large one, and Kragh recognizes from the outset that he has to be selective and concentrate on those subjects that define twentieth-century physics. For the early part of the century the author relies on carefully chosen secondary sources, to avoid the near-impossible task of absorbing a multitude of original papers. The recent period is more difficult, and the sources are articles, reviews, and the recollections of physicists. The book is in three main sections, roughly to the end of World War I, to the end of World War II, and up to 1995, plus a retrospective summary. It deals with more than just discoveries in physics, looking also at physicists and institutions, and at their interactions with the rest of society. The broad outlines of many discoveries are often known to physicists who have no special interest in history, and Kragh is careful to point out where these conventional accounts are inadequate. The first chapters set the scene at the end of the nineteenth century, acknowledging that there was a belief that all the grand underlying principles had been established, but also pointing out that there was a ferment of attempts to reinterpret physics in terms of concepts like vortices and hyperspaces. The history begins with the mould-breaking discoveries of x-rays, radioactivity and the electron. The chapters that follow look at theories about atomic structure, and at quantum physics, relativity and
Quantum walks, quantum gates, and quantum computers
International Nuclear Information System (INIS)
Hines, Andrew P.; Stamp, P. C. E.
2007-01-01
The physics of quantum walks on graphs is formulated in Hamiltonian language, both for simple quantum walks and for composite walks, where extra discrete degrees of freedom live at each node of the graph. It is shown how to map between quantum walk Hamiltonians and Hamiltonians for qubit systems and quantum circuits; this is done for both single-excitation and multiexcitation encodings. Specific examples of spin chains, as well as static and dynamic systems of qubits, are mapped to quantum walks, and walks on hyperlattices and hypercubes are mapped to various gate systems. We also show how to map a quantum circuit performing the quantum Fourier transform, the key element of Shor's algorithm, to a quantum walk system doing the same. The results herein are an essential preliminary to a Hamiltonian formulation of quantum walks in which coupling to a dynamic quantum environment is included
Physical state condition in quantum general relativity as a consequence of BRST symmetry
International Nuclear Information System (INIS)
Castellana, Michele; Montani, Giovanni
2008-01-01
Quantization of systems with constraints can be carried out with several methods. In the Dirac formulation the classical generators of gauge transformations are required to annihilate physical quantum states to ensure their gauge invariance. Carrying on BRST symmetry it is possible to get a condition on physical states which, different from the Dirac method, requires them to be invariant under the BRST transformation. Employing this method for the action of general relativity expressed in terms of the spin connection and tetrad fields with path integral methods, we construct the generator of the BRST transformation associated with the underlying local Lorentz symmetry of the theory and write a physical state condition following from BRST invariance. This derivation is based on the general results on the dependence of the effective action used in path integrals and consequently of Green's functions on the gauge-fixing functionals used in the DeWitt-Faddeev-Popov method. The condition we gain differs from the one obtained within Ashtekar's canonical formulation, showing how we recover the latter only by a suitable choice of the gauge-fixing functionals. Finally we discuss how it should be possible to obtain all of the requested physical state conditions associated with all the underlying gauge symmetries of the classical theory using our approach
The scientific heritage of Alexandru Proca and the Quantum Physics revolution
International Nuclear Information System (INIS)
Calboreanu, Alexandru
2004-01-01
'One of the most prodigious phenomena of the recent history of Physics was the extraordinary influence of Einstein's ideas not only on the contemporary scientific theory but also on its applications'. These words have been uttered by outstanding physicist, however slightly known even in his native country, at the first jubilee of one of the greatest landmarks in physics development - the 'Annus Mirrabilis 1905'. The utterance belongs to Alexander Proca, at the time (1955) Directeur de Recherche at the CNRS - France, and were written for the French weekly magazine 'Le Figaro Litteraire'. Proca was one of the great minds which entered physics at the right time, but probably not in the right place. He belonged to the 'golden generation' that shaped the structure not only of physics but also of entire science and applications, as stated in his own words. Proca devoted his most creative years of his life to the development of a sound relativistic quantum theory. In the effervescent years of the fourth decade of the 20th century, among outstanding scientists like de Broglie, Schroedinger, Pauli, Heisenberg, Bohr, or Dirac, Proca found an elegant and original path that remains even today modern and valid. This is why it is a fact of gratitude to revive his memory after half a century elapsed since he paid homage to the memory of Einstein. (author)
International Nuclear Information System (INIS)
Kilin, Sergei Ya
1999-01-01
A new research direction known as quantum information is a multidisciplinary subject which involves quantum mechanics, optics, information theory, programming, discrete mathematics, laser physics and spectroscopy, and depends heavily on contributions from such areas as quantum computing, quantum teleportation and quantum cryptography, decoherence studies, and single-molecule and impurity spectroscopy. Some new results achieved in this rapidly growing field are discussed. (reviews of topical problems)
Energy Technology Data Exchange (ETDEWEB)
Kilin, Sergei Ya [B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk (Belarus)
1999-05-31
A new research direction known as quantum information is a multidisciplinary subject which involves quantum mechanics, optics, information theory, programming, discrete mathematics, laser physics and spectroscopy, and depends heavily on contributions from such areas as quantum computing, quantum teleportation and quantum cryptography, decoherence studies, and single-molecule and impurity spectroscopy. Some new results achieved in this rapidly growing field are discussed. (reviews of topical problems)
International Nuclear Information System (INIS)
Heusler, Stefan
2006-01-01
The main focus of the second, enlarged edition of the book Mathematica for Theoretical Physics is on computational examples using the computer program Mathematica in various areas in physics. It is a notebook rather than a textbook. Indeed, the book is just a printout of the Mathematica notebooks included on the CD. The second edition is divided into two volumes, the first covering classical mechanics and nonlinear dynamics, the second dealing with examples in electrodynamics, quantum mechanics, general relativity and fractal geometry. The second volume is not suited for newcomers because basic and simple physical ideas which lead to complex formulas are not explained in detail. Instead, the computer technology makes it possible to write down and manipulate formulas of practically any length. For researchers with experience in computing, the book contains a lot of interesting and non-trivial examples. Most of the examples discussed are standard textbook problems, but the power of Mathematica opens the path to more sophisticated solutions. For example, the exact solution for the perihelion shift of Mercury within general relativity is worked out in detail using elliptic functions. The virial equation of state for molecules' interaction with Lennard-Jones-like potentials is discussed, including both classical and quantum corrections to the second virial coefficient. Interestingly, closed solutions become available using sophisticated computing methods within Mathematica. In my opinion, the textbook should not show formulas in detail which cover three or more pages-these technical data should just be contained on the CD. Instead, the textbook should focus on more detailed explanation of the physical concepts behind the technicalities. The discussion of the virial equation would benefit much from replacing 15 pages of Mathematica output with 15 pages of further explanation and motivation. In this combination, the power of computing merged with physical intuition would
Photonic topological boundary pumping as a probe of 4D quantum Hall physics.
Zilberberg, Oded; Huang, Sheng; Guglielmon, Jonathan; Wang, Mohan; Chen, Kevin P; Kraus, Yaacov E; Rechtsman, Mikael C
2018-01-03
When a two-dimensional (2D) electron gas is placed in a perpendicular magnetic field, its in-plane transverse conductance becomes quantized; this is known as the quantum Hall effect. It arises from the non-trivial topology of the electronic band structure of the system, where an integer topological invariant (the first Chern number) leads to quantized Hall conductance. It has been shown theoretically that the quantum Hall effect can be generalized to four spatial dimensions, but so far this has not been realized experimentally because experimental systems are limited to three spatial dimensions. Here we use tunable 2D arrays of photonic waveguides to realize a dynamically generated four-dimensional (4D) quantum Hall system experimentally. The inter-waveguide separation in the array is constructed in such a way that the propagation of light through the device samples over momenta in two additional synthetic dimensions, thus realizing a 2D topological pump. As a result, the band structure has 4D topological invariants (known as second Chern numbers) that support a quantized bulk Hall response with 4D symmetry. In a finite-sized system, the 4D topological bulk response is carried by localized edge modes that cross the sample when the synthetic momenta are modulated. We observe this crossing directly through photon pumping of our system from edge to edge and corner to corner. These crossings are equivalent to charge pumping across a 4D system from one three-dimensional hypersurface to the spatially opposite one and from one 2D hyperedge to another. Our results provide a platform for the study of higher-dimensional topological physics.
Photonic topological boundary pumping as a probe of 4D quantum Hall physics
Zilberberg, Oded; Huang, Sheng; Guglielmon, Jonathan; Wang, Mohan; Chen, Kevin P.; Kraus, Yaacov E.; Rechtsman, Mikael C.
2018-01-01
When a two-dimensional (2D) electron gas is placed in a perpendicular magnetic field, its in-plane transverse conductance becomes quantized; this is known as the quantum Hall effect. It arises from the non-trivial topology of the electronic band structure of the system, where an integer topological invariant (the first Chern number) leads to quantized Hall conductance. It has been shown theoretically that the quantum Hall effect can be generalized to four spatial dimensions, but so far this has not been realized experimentally because experimental systems are limited to three spatial dimensions. Here we use tunable 2D arrays of photonic waveguides to realize a dynamically generated four-dimensional (4D) quantum Hall system experimentally. The inter-waveguide separation in the array is constructed in such a way that the propagation of light through the device samples over momenta in two additional synthetic dimensions, thus realizing a 2D topological pump. As a result, the band structure has 4D topological invariants (known as second Chern numbers) that support a quantized bulk Hall response with 4D symmetry. In a finite-sized system, the 4D topological bulk response is carried by localized edge modes that cross the sample when the synthetic momenta are modulated. We observe this crossing directly through photon pumping of our system from edge to edge and corner to corner. These crossings are equivalent to charge pumping across a 4D system from one three-dimensional hypersurface to the spatially opposite one and from one 2D hyperedge to another. Our results provide a platform for the study of higher-dimensional topological physics.